51123816 has 24 divisors (see below), whose sum is σ = 138460530. Its totient is φ = 17041248.

The previous prime is 51123803. The next prime is 51123817. The reversal of 51123816 is 61832115.

It can be written as a sum of positive squares in only one way, i.e., 27562500 + 23561316 = 5250^2 + 4854^2 .

It is a tau number, because it is divible by the number of its divisors (24).

It is a super-2 number, since 2×51123816² = 5227289124803712, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 51123816.

It is not an unprimeable number, because it can be changed into a prime (51123817) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 354955 + ... + 355098.

Almost surely, 2^51123816 is an apocalyptic number.

It is an amenable number.

51123816 is an abundant number, since it is smaller than the sum of its proper divisors (87336714).

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

51123816 is a wasteful number, since it uses less digits than its factorization.

51123816 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 710065 (or 710058 counting only the distinct ones).

The product of its digits is 1440, while the sum is 27.

The square root of 51123816 is about 7150.0920273798. The cubic root of 51123816 is about 371.1428408879.

The spelling of 51123816 in words is "fifty-one million, one hundred twenty-three thousand, eight hundred sixteen".