51699520 has 28 divisors (see below), whose sum is σ = 123110244. Its totient is φ = 20679680.

The previous prime is 51699503. The next prime is 51699523. The reversal of 51699520 is 2599615.

It can be written as a sum of positive squares in 2 ways, for example, as 25321024 + 26378496 = 5032^2 + 5136^2 .

It is a Smith number, since the sum of its digits (37) coincides with the sum of the digits of its prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 51699520.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51699523) 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, 80461 + ... + 81100.

Almost surely, 2^51699520 is an apocalyptic number.

It is an amenable number.

51699520 is an abundant number, since it is smaller than the sum of its proper divisors (71410724).

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

51699520 is a wasteful number, since it uses less digits than its factorization.

51699520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 161578 (or 161568 counting only the distinct ones).

The product of its (nonzero) digits is 24300, while the sum is 37.

The square root of 51699520 is about 7190.2378263866. The cubic root of 51699520 is about 372.5307873597.

The spelling of 51699520 in words is "fifty-one million, six hundred ninety-nine thousand, five hundred twenty".