51657768 has 48 divisors (see below), whose sum is σ = 140954580. Its totient is φ = 17090304.

The previous prime is 51657757. The next prime is 51657779. The reversal of 51657768 is 86775615.

51657768 is a `hidden beast` number, since 5 + 16 + 577 + 68 = 666.

It is an interprime number because it is at equal distance from previous prime (51657757) and next prime (51657779).

It can be written as a sum of positive squares in 2 ways, for example, as 48692484 + 2965284 = 6978^2 + 1722^2 .

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, 7246 + ... + 12482.

Almost surely, 2^51657768 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 51657768, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (70477290).

51657768 is an abundant number, since it is smaller than the sum of its proper divisors (89296812).

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

51657768 is a wasteful number, since it uses less digits than its factorization.

51657768 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5386 (or 5379 counting only the distinct ones).

The product of its digits is 352800, while the sum is 45.

The square root of 51657768 is about 7187.3338589494. Note that the first 3 decimals coincide. The cubic root of 51657768 is about 372.4304763422.

It can be divided in two parts, 51657 and 768, that added together give a palindrome (52425).

The spelling of 51657768 in words is "fifty-one million, six hundred fifty-seven thousand, seven hundred sixty-eight".