51686020 has 12 divisors (see below), whose sum is σ = 108540684. Its totient is φ = 20674400.

The previous prime is 51686017. The next prime is 51686039. The reversal of 51686020 is 2068615.

It can be written as a sum of positive squares in 2 ways, for example, as 28472896 + 23213124 = 5336^2 + 4818^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 51686020.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1292131 + ... + 1292170.

It is an arithmetic number, because the mean of its divisors is an integer number (9045057).

Almost surely, 2^51686020 is an apocalyptic number.

It is an amenable number.

51686020 is an abundant number, since it is smaller than the sum of its proper divisors (56854664).

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

51686020 is a wasteful number, since it uses less digits than its factorization.

51686020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2584310 (or 2584308 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 28.

The square root of 51686020 is about 7189.2989922523. The cubic root of 51686020 is about 372.4983589256.

The spelling of 51686020 in words is "fifty-one million, six hundred eighty-six thousand, twenty".