2156547816 has 24 divisors (see below), whose sum is σ = 5840650530. Its totient is φ = 718849248.

The previous prime is 2156547791. The next prime is 2156547857. The reversal of 2156547816 is 6187456512.

2156547816 is a `hidden beast` number, since 2 + 1 + 565 + 4 + 7 + 81 + 6 = 666.

It can be written as a sum of positive squares in only one way, i.e., 1835779716 + 320768100 = 42846^2 + 17910^2 .

It is a tau number, because it is divible by the number of its divisors (24).

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 14975955 + ... + 14976098.

Almost surely, 2^2156547816 is an apocalyptic number.

It is an amenable number.

2156547816 is an abundant number, since it is smaller than the sum of its proper divisors (3684102714).

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

2156547816 is a wasteful number, since it uses less digits than its factorization.

2156547816 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29952065 (or 29952058 counting only the distinct ones).

The product of its digits is 403200, while the sum is 45.

The square root of 2156547816 is about 46438.6457166873. The cubic root of 2156547816 is about 1291.9717889472.

The spelling of 2156547816 in words is "two billion, one hundred fifty-six million, five hundred forty-seven thousand, eight hundred sixteen".