1221131120 has 40 divisors (see below), whose sum is σ = 3097234800. Its totient is φ = 444047360.

The previous prime is 1221131113. The next prime is 1221131141. The reversal of 1221131120 is 211311221.

It is a tau number, because it is divible by the number of its divisors (40).

It is a super-2 number, since 2×1221131120² = 2982322424464908800, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1221131095 and 1221131104.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 692945 + ... + 694704.

It is an arithmetic number, because the mean of its divisors is an integer number (77430870).

Almost surely, 2^1221131120 is an apocalyptic number.

1221131120 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1221131120 is an abundant number, since it is smaller than the sum of its proper divisors (1876103680).

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

1221131120 is a wasteful number, since it uses less digits than its factorization.

1221131120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1387673 (or 1387667 counting only the distinct ones).

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

The square root of 1221131120 is about 34944.6865775042. The cubic root of 1221131120 is about 1068.8598563819.

Adding to 1221131120 its reverse (211311221), we get a palindrome (1432442341).

The spelling of 1221131120 in words is "one billion, two hundred twenty-one million, one hundred thirty-one thousand, one hundred twenty".