2156539771 has 12 divisors (see below), whose sum is σ = 2246764432. Its totient is φ = 2069352000.

The previous prime is 2156539757. The next prime is 2156539817. The reversal of 2156539771 is 1779356512.

It is a happy number.

It is not a de Polignac number, because 2156539771 - 2⁷ = 2156539643 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2156539711) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 92026 + ... + 113056.

Almost surely, 2^2156539771 is an apocalyptic number.

2156539771 is a deficient number, since it is larger than the sum of its proper divisors (90224661).

2156539771 is an equidigital number, since it uses as much as digits as its factorization.

2156539771 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21174 (or 21133 counting only the distinct ones).

The product of its digits is 396900, while the sum is 46.

The square root of 2156539771 is about 46438.5590969401. The cubic root of 2156539771 is about 1291.9701823786.

The spelling of 2156539771 in words is "two billion, one hundred fifty-six million, five hundred thirty-nine thousand, seven hundred seventy-one".