2156994897 has 16 divisors (see below), whose sum is σ = 2909586432. Its totient is φ = 1421297280.

The previous prime is 2156994887. The next prime is 2156994941. The reversal of 2156994897 is 7984996512.

It is not a de Polignac number, because 2156994897 - 2⁷ = 2156994769 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 2156994897.

It is not an unprimeable number, because it can be changed into a prime (2156994877) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 77973 + ... + 101949.

It is an arithmetic number, because the mean of its divisors is an integer number (181849152).

Almost surely, 2^2156994897 is an apocalyptic number.

It is an amenable number.

2156994897 is a deficient number, since it is larger than the sum of its proper divisors (752591535).

2156994897 is a wasteful number, since it uses less digits than its factorization.

2156994897 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24328.

The product of its digits is 9797760, while the sum is 60.

The square root of 2156994897 is about 46443.4591411966. The cubic root of 2156994897 is about 1292.0610637477.

The spelling of 2156994897 in words is "two billion, one hundred fifty-six million, nine hundred ninety-four thousand, eight hundred ninety-seven".