51747440 has 20 divisors (see below), whose sum is σ = 120312984. Its totient is φ = 20698944.

The previous prime is 51747433. The next prime is 51747457. The reversal of 51747440 is 4474715.

It is a tau number, because it is divible by the number of its divisors (20).

It is a junction number, because it is equal to n+sod(n) for n = 51747397 and 51747406.

It is a congruent number.

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, 323342 + ... + 323501.

Almost surely, 2^51747440 is an apocalyptic number.

It is an amenable number.

51747440 is an abundant number, since it is smaller than the sum of its proper divisors (68565544).

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

51747440 is a wasteful number, since it uses less digits than its factorization.

51747440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 646856 (or 646850 counting only the distinct ones).

The product of its (nonzero) digits is 15680, while the sum is 32.

The square root of 51747440 is about 7193.5693504685. The cubic root of 51747440 is about 372.6458507273.

The spelling of 51747440 in words is "fifty-one million, seven hundred forty-seven thousand, four hundred forty".