51561136 has 80 divisors (see below), whose sum is σ = 121599360. Its totient is φ = 20874240.

The previous prime is 51561131. The next prime is 51561137. The reversal of 51561136 is 63116515.

It is a super-2 number, since 2×51561136² = 5317101491220992, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (51561131) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 56395 + ... + 57301.

It is an arithmetic number, because the mean of its divisors is an integer number (1519992).

Almost surely, 2^51561136 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 51561136, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (60799680).

51561136 is an abundant number, since it is smaller than the sum of its proper divisors (70038224).

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

51561136 is a wasteful number, since it uses less digits than its factorization.

51561136 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 962 (or 956 counting only the distinct ones).

The product of its digits is 2700, while the sum is 28.

The square root of 51561136 is about 7180.6083307753. The cubic root of 51561136 is about 372.1981062204.

The spelling of 51561136 in words is "fifty-one million, five hundred sixty-one thousand, one hundred thirty-six".