51186520 has 64 divisors (see below), whose sum is σ = 143596800. Its totient is φ = 15953280.

The previous prime is 51186511. The next prime is 51186521. The reversal of 51186520 is 2568115.

51186520 = 8² + 9² + ... + 535².

It is a Harshad number since it is a multiple of its sum of digits (28).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51186521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5230 + ... + 11389.

It is an arithmetic number, because the mean of its divisors is an integer number (2243700).

Almost surely, 2^51186520 is an apocalyptic number.

It is an amenable number.

51186520 is an abundant number, since it is smaller than the sum of its proper divisors (92410280).

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

51186520 is a wasteful number, since it uses less digits than its factorization.

51186520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16648 (or 16644 counting only the distinct ones).

The product of its (nonzero) digits is 2400, while the sum is 28.

The square root of 51186520 is about 7154.4755223566. The cubic root of 51186520 is about 371.2945160071.

The spelling of 51186520 in words is "fifty-one million, one hundred eighty-six thousand, five hundred twenty".