51657520 has 40 divisors (see below), whose sum is σ = 120545856. Its totient is φ = 20587008.

The previous prime is 51657511. The next prime is 51657527. The reversal of 51657520 is 2575615.

It is a tau number, because it is divible by the number of its divisors (40).

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (51657527) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 24009 + ... + 26071.

Almost surely, 2^51657520 is an apocalyptic number.

It is an amenable number.

51657520 is an abundant number, since it is smaller than the sum of its proper divisors (68888336).

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

51657520 is a wasteful number, since it uses less digits than its factorization.

51657520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2389 (or 2383 counting only the distinct ones).

The product of its (nonzero) digits is 10500, while the sum is 31.

The square root of 51657520 is about 7187.3166063559. The cubic root of 51657520 is about 372.4298803498.

The spelling of 51657520 in words is "fifty-one million, six hundred fifty-seven thousand, five hundred twenty".