51561156 has 24 divisors (see below), whose sum is σ = 122580864. Its totient is φ = 16862560.

The previous prime is 51561151. The next prime is 51561157. The reversal of 51561156 is 65116515.

It is a hoax number, since the sum of its digits (30) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (51561151) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 39900 + ... + 41171.

It is an arithmetic number, because the mean of its divisors is an integer number (5107536).

Almost surely, 2^51561156 is an apocalyptic number.

It is an amenable number.

51561156 is an abundant number, since it is smaller than the sum of its proper divisors (71019708).

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

51561156 is a wasteful number, since it uses less digits than its factorization.

51561156 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 81131 (or 81129 counting only the distinct ones).

The product of its digits is 4500, while the sum is 30.

The square root of 51561156 is about 7180.6097234149. The cubic root of 51561156 is about 372.1981543442.

The spelling of 51561156 in words is "fifty-one million, five hundred sixty-one thousand, one hundred fifty-six".