1321561136 has 20 divisors (see below), whose sum is σ = 2926314192. Its totient is φ = 566383296.

The previous prime is 1321561133. The next prime is 1321561151. The reversal of 1321561136 is 6311651231.

It is a super-2 number, since 2×1321561136² = 3493047672371220992, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1321561099 and 1321561108.

It is not an unprimeable number, because it can be changed into a prime (1321561133) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5899715 + ... + 5899938.

Almost surely, 2^1321561136 is an apocalyptic number.

1321561136 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

1321561136 is an abundant number, since it is smaller than the sum of its proper divisors (1604753056).

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

1321561136 is a wasteful number, since it uses less digits than its factorization.

1321561136 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11799668 (or 11799662 counting only the distinct ones).

The product of its digits is 3240, while the sum is 29.

The square root of 1321561136 is about 36353.2823277349. The cubic root of 1321561136 is about 1097.3935910726.

The spelling of 1321561136 in words is "one billion, three hundred twenty-one million, five hundred sixty-one thousand, one hundred thirty-six".