51657660 has 36 divisors (see below), whose sum is σ = 156695448. Its totient is φ = 13775328.

The previous prime is 51657649. The next prime is 51657673. The reversal of 51657660 is 6675615.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (36).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 143314 + ... + 143673.

Almost surely, 2^51657660 is an apocalyptic number.

It is an amenable number.

51657660 is an abundant number, since it is smaller than the sum of its proper divisors (105037788).

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

51657660 is a wasteful number, since it uses less digits than its factorization.

51657660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 287002 (or 286997 counting only the distinct ones).

The product of its (nonzero) digits is 37800, while the sum is 36.

The square root of 51657660 is about 7187.3263457283. The cubic root of 51657660 is about 372.4302167973.

It can be divided in two parts, 516576 and 60, that added together give a triangular number (516636 = T₁₀₁₆).

The spelling of 51657660 in words is "fifty-one million, six hundred fifty-seven thousand, six hundred sixty".