1321981320 has 64 divisors (see below), whose sum is σ = 4326488640. Its totient is φ = 320480000.

The previous prime is 1321981301. The next prime is 1321981337. The reversal of 1321981320 is 231891231.

1321981320 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×1321981320² = 3495269220857884800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 499431 + ... + 502070.

It is an arithmetic number, because the mean of its divisors is an integer number (67601385).

Almost surely, 2^1321981320 is an apocalyptic number.

1321981320 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1321981320 is an abundant number, since it is smaller than the sum of its proper divisors (3004507320).

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

1321981320 is a wasteful number, since it uses less digits than its factorization.

1321981320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1001526 (or 1001522 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 30.

The square root of 1321981320 is about 36359.0610439819. The cubic root of 1321981320 is about 1097.5098824182.

1321981320 divided by its sum of digits (30) gives a palindrome (44066044).

The spelling of 1321981320 in words is "one billion, three hundred twenty-one million, nine hundred eighty-one thousand, three hundred twenty".