51816618 has 48 divisors (see below), whose sum is σ = 133954560. Its totient is φ = 14803992.

The previous prime is 51816599. The next prime is 51816623. The reversal of 51816618 is 81661815.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 7146 + ... + 12437.

It is an arithmetic number, because the mean of its divisors is an integer number (2790720).

Almost surely, 2^51816618 is an apocalyptic number.

51816618 is an abundant number, since it is smaller than the sum of its proper divisors (82137942).

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

51816618 is a wasteful number, since it uses less digits than its factorization.

51816618 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19608 (or 19595 counting only the distinct ones).

The product of its digits is 11520, while the sum is 36.

The square root of 51816618 is about 7198.3760668640. The cubic root of 51816618 is about 372.8118326308.

The spelling of 51816618 in words is "fifty-one million, eight hundred sixteen thousand, six hundred eighteen".