1121211220 has 24 divisors (see below), whose sum is σ = 2394453600. Its totient is φ = 440882592.

The previous prime is 1121211127. The next prime is 1121211229. The reversal of 1121211220 is 221121211.

It is a super-2 number, since 2×1121211220² = 2514229199707776800, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 1121211220.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1121211229) 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 7 ways as a sum of consecutive naturals, for example, 473910 + ... + 476269.

It is an arithmetic number, because the mean of its divisors is an integer number (99768900).

Almost surely, 2^1121211220 is an apocalyptic number.

1121211220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1121211220 is an abundant number, since it is smaller than the sum of its proper divisors (1273242380).

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

1121211220 is a wasteful number, since it uses less digits than its factorization.

1121211220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 950247 (or 950245 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 13.

The square root of 1121211220 is about 33484.4922314793. The cubic root of 1121211220 is about 1038.8730457812.

Adding to 1121211220 its reverse (221121211), we get a palindrome (1342332431).

Subtracting from 1121211220 its reverse (221121211), we obtain a palindrome (900090009).

The spelling of 1121211220 in words is "one billion, one hundred twenty-one million, two hundred eleven thousand, two hundred twenty".