2156637506 has 4 divisors (see below), whose sum is σ = 3234956262. Its totient is φ = 1078318752.

The previous prime is 2156637491. The next prime is 2156637521. The reversal of 2156637506 is 6057366512.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (2156637491) and next prime (2156637521).

It can be written as a sum of positive squares in only one way, i.e., 2099014225 + 57623281 = 45815^2 + 7591^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 539159375 + ... + 539159378.

Almost surely, 2^2156637506 is an apocalyptic number.

2156637506 is a deficient number, since it is larger than the sum of its proper divisors (1078318756).

2156637506 is a wasteful number, since it uses less digits than its factorization.

2156637506 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1078318755.

The product of its (nonzero) digits is 226800, while the sum is 41.

The square root of 2156637506 is about 46439.6113894163. The cubic root of 2156637506 is about 1291.9896995699.

The spelling of 2156637506 in words is "two billion, one hundred fifty-six million, six hundred thirty-seven thousand, five hundred six".