51536640 has 72 divisors (see below), whose sum is σ = 164607408. Its totient is φ = 13742080.

The previous prime is 51536623. The next prime is 51536659. The reversal of 51536640 is 4663515.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 51536598 and 51536607.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2871 + ... + 10550.

It is an arithmetic number, because the mean of its divisors is an integer number (2286214).

Almost surely, 2^51536640 is an apocalyptic number.

It is an amenable number.

51536640 is an abundant number, since it is smaller than the sum of its proper divisors (113070768).

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

51536640 is a wasteful number, since it uses less digits than its factorization.

51536640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13445 (or 13431 counting only the distinct ones).

The product of its (nonzero) digits is 10800, while the sum is 30.

The square root of 51536640 is about 7178.9024230728. The cubic root of 51536640 is about 372.1391547843.

The spelling of 51536640 in words is "fifty-one million, five hundred thirty-six thousand, six hundred forty".