1211231120 has 80 divisors (see below), whose sum is σ = 3080749248. Its totient is φ = 439211520.

The previous prime is 1211231117. The next prime is 1211231123. The reversal of 1211231120 is 211321121.

It is an interprime number because it is at equal distance from previous prime (1211231117) and next prime (1211231123).

It is a tau number, because it is divible by the number of its divisors (80).

It is a super-3 number, since 3×1211231120³ (a number of 28 digits) contains 333 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1211231095 and 1211231104.

It is not an unprimeable number, because it can be changed into a prime (1211231123) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 347627 + ... + 351093.

Almost surely, 2^1211231120 is an apocalyptic number.

1211231120 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1211231120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1540374624).

1211231120 is an abundant number, since it is smaller than the sum of its proper divisors (1869518128).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1211231120 is a wasteful number, since it uses less digits than its factorization.

1211231120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3888 (or 3882 counting only the distinct ones).

The product of its (nonzero) digits is 24, while the sum is 14.

The square root of 1211231120 is about 34802.7458686811. The cubic root of 1211231120 is about 1065.9635148794.

Adding to 1211231120 its reverse (211321121), we get a palindrome (1422552241).

Subtracting from 1211231120 its reverse (211321121), we obtain a palindrome (999909999).

The spelling of 1211231120 in words is "one billion, two hundred eleven million, two hundred thirty-one thousand, one hundred twenty".