51039684 has 18 divisors (see below), whose sum is σ = 129017070. Its totient is φ = 17013216.

The previous prime is 51039683. The next prime is 51039773. The reversal of 51039684 is 48693015.

It can be written as a sum of positive squares in only one way, i.e., 41602500 + 9437184 = 6450^2 + 3072^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is a Harshad number since it is a multiple of its sum of digits (36), and also a Moran number because the ratio is a prime number: 1417769 = 51039684 / (5 + 1 + 0 + 3 + 9 + 6 + 8 + 4).

It is not an unprimeable number, because it can be changed into a prime (51039683) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 708849 + ... + 708920.

It is an arithmetic number, because the mean of its divisors is an integer number (7167615).

Almost surely, 2^51039684 is an apocalyptic number.

It is an amenable number.

51039684 is an abundant number, since it is smaller than the sum of its proper divisors (77977386).

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

51039684 is a wasteful number, since it uses less digits than its factorization.

51039684 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1417779 (or 1417774 counting only the distinct ones).

The product of its (nonzero) digits is 25920, while the sum is 36.

The square root of 51039684 is about 7144.2063240083. The cubic root of 51039684 is about 370.9391384775.

The spelling of 51039684 in words is "fifty-one million, thirty-nine thousand, six hundred eighty-four".