51657664 has 14 divisors (see below), whose sum is σ = 102508304. Its totient is φ = 25828800.

The previous prime is 51657649. The next prime is 51657673. The reversal of 51657664 is 46675615.

It is a congruent number.

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 403512 + ... + 403639.

Almost surely, 2^51657664 is an apocalyptic number.

It is an amenable number.

51657664 is a deficient number, since it is larger than the sum of its proper divisors (50850640).

51657664 is an equidigital number, since it uses as much as digits as its factorization.

51657664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 807163 (or 807153 counting only the distinct ones).

The product of its digits is 151200, while the sum is 40.

The square root of 51657664 is about 7187.3266239959. The cubic root of 51657664 is about 372.4302264101.

The spelling of 51657664 in words is "fifty-one million, six hundred fifty-seven thousand, six hundred sixty-four".