51639684 has 48 divisors (see below), whose sum is σ = 122967936. Its totient is φ = 16864000.

The previous prime is 51639683. The next prime is 51639703. The reversal of 51639684 is 48693615.

51639684 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not an unprimeable number, because it can be changed into a prime (51639683) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 165889 + ... + 166199.

It is an arithmetic number, because the mean of its divisors is an integer number (2561832).

Almost surely, 2^51639684 is an apocalyptic number.

It is an amenable number.

51639684 is an abundant number, since it is smaller than the sum of its proper divisors (71328252).

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

51639684 is a wasteful number, since it uses less digits than its factorization.

51639684 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 556 (or 554 counting only the distinct ones).

The product of its digits is 155520, while the sum is 42.

The square root of 51639684 is about 7186.0757023566. The cubic root of 51639684 is about 372.3870119607.

The spelling of 51639684 in words is "fifty-one million, six hundred thirty-nine thousand, six hundred eighty-four".