51775668 has 72 divisors (see below), whose sum is σ = 156094848. Its totient is φ = 14148288.

The previous prime is 51775667. The next prime is 51775679. The reversal of 51775668 is 86657715.

51775668 is a `hidden beast` number, since 517 + 75 + 6 + 68 = 666.

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51775667) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1330 + ... + 10262.

It is an arithmetic number, because the mean of its divisors is an integer number (2167984).

Almost surely, 2^51775668 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 51775668, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (78047424).

51775668 is an abundant number, since it is smaller than the sum of its proper divisors (104319180).

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

51775668 is a wasteful number, since it uses less digits than its factorization.

51775668 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8973 (or 8968 counting only the distinct ones).

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

The square root of 51775668 is about 7195.5311131285. The cubic root of 51775668 is about 372.7135972990.

The spelling of 51775668 in words is "fifty-one million, seven hundred seventy-five thousand, six hundred sixty-eight".