2156640996 has 12 divisors (see below), whose sum is σ = 5032162352. Its totient is φ = 718880328.

The previous prime is 2156640991. The next prime is 2156641033. The reversal of 2156640996 is 6990466512.

It is a tau number, because it is divible by the number of its divisors (12).

It is a super-2 number, since 2×2156640996² = 9302200771255744032, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (2156640991) 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, 89860030 + ... + 89860053.

Almost surely, 2^2156640996 is an apocalyptic number.

It is an amenable number.

2156640996 is an abundant number, since it is smaller than the sum of its proper divisors (2875521356).

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

2156640996 is a wasteful number, since it uses less digits than its factorization.

2156640996 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 179720090 (or 179720088 counting only the distinct ones).

The product of its (nonzero) digits is 699840, while the sum is 48.

The square root of 2156640996 is about 46439.6489650816. The cubic root of 2156640996 is about 1291.9903964946.

The spelling of 2156640996 in words is "two billion, one hundred fifty-six million, six hundred forty thousand, nine hundred ninety-six".