51561318 has 16 divisors (see below), whose sum is σ = 103451760. Its totient is φ = 17132256.

The previous prime is 51561317. The next prime is 51561319. The reversal of 51561318 is 81316515.

It is an interprime number because it is at equal distance from previous prime (51561317) and next prime (51561319).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51561311) 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, 11653 + ... + 15456.

It is an arithmetic number, because the mean of its divisors is an integer number (6465735).

Almost surely, 2^51561318 is an apocalyptic number.

51561318 is an abundant number, since it is smaller than the sum of its proper divisors (51890442).

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

51561318 is a wasteful number, since it uses less digits than its factorization.

51561318 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27431.

The product of its digits is 3600, while the sum is 30.

The square root of 51561318 is about 7180.6210037851. The cubic root of 51561318 is about 372.1985441470.

The spelling of 51561318 in words is "fifty-one million, five hundred sixty-one thousand, three hundred eighteen".