51661868 has 12 divisors (see below), whose sum is σ = 90458592. Its totient is φ = 25816560.

The previous prime is 51661867. The next prime is 51661889. The reversal of 51661868 is 86816615.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (51661867) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12413 + ... + 16043.

It is an arithmetic number, because the mean of its divisors is an integer number (7538216).

Almost surely, 2^51661868 is an apocalyptic number.

It is an amenable number.

51661868 is a deficient number, since it is larger than the sum of its proper divisors (38796724).

51661868 is a wasteful number, since it uses less digits than its factorization.

51661868 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7192 (or 7190 counting only the distinct ones).

The product of its digits is 69120, while the sum is 41.

The square root of 51661868 is about 7187.6190772745. The cubic root of 51661868 is about 372.4403291653.

The spelling of 51661868 in words is "fifty-one million, six hundred sixty-one thousand, eight hundred sixty-eight".