2156977249 has 4 divisors (see below), whose sum is σ = 2465116864. Its totient is φ = 1848837636.

The previous prime is 2156977171. The next prime is 2156977259. The reversal of 2156977249 is 9427796512.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 2156977249 - 2²⁷ = 2022759521 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 2156977196 and 2156977205.

It is not an unprimeable number, because it can be changed into a prime (2156977259) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 154069797 + ... + 154069810.

It is an arithmetic number, because the mean of its divisors is an integer number (616279216).

Almost surely, 2^2156977249 is an apocalyptic number.

It is an amenable number.

2156977249 is a deficient number, since it is larger than the sum of its proper divisors (308139615).

2156977249 is an equidigital number, since it uses as much as digits as its factorization.

2156977249 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 308139614.

The product of its digits is 1905120, while the sum is 52.

The square root of 2156977249 is about 46443.2691463467. The cubic root of 2156977249 is about 1292.0575399631.

The spelling of 2156977249 in words is "two billion, one hundred fifty-six million, nine hundred seventy-seven thousand, two hundred forty-nine".