2156614561 has 4 divisors (see below), whose sum is σ = 2206768432. Its totient is φ = 2106460692.

The previous prime is 2156614531. The next prime is 2156614567. The reversal of 2156614561 is 1654166512.

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 2156614561 - 2⁵ = 2156614529 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 2156614561.

It is not an unprimeable number, because it can be changed into a prime (2156614567) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 25076871 + ... + 25076956.

It is an arithmetic number, because the mean of its divisors is an integer number (551692108).

Almost surely, 2^2156614561 is an apocalyptic number.

It is an amenable number.

2156614561 is a deficient number, since it is larger than the sum of its proper divisors (50153871).

2156614561 is an equidigital number, since it uses as much as digits as its factorization.

2156614561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 50153870.

The product of its digits is 43200, while the sum is 37.

The square root of 2156614561 is about 46439.3643475016. The cubic root of 2156614561 is about 1291.9851176210.

The spelling of 2156614561 in words is "two billion, one hundred fifty-six million, six hundred fourteen thousand, five hundred sixty-one".