51999456 has 24 divisors (see below), whose sum is σ = 136498824. Its totient is φ = 17333120.

The previous prime is 51999397. The next prime is 51999463. The reversal of 51999456 is 65499915.

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

It is a Harshad number since it is a multiple of its sum of digits (48).

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, 270735 + ... + 270926.

It is an arithmetic number, because the mean of its divisors is an integer number (5687451).

Almost surely, 2^51999456 is an apocalyptic number.

It is an amenable number.

51999456 is an abundant number, since it is smaller than the sum of its proper divisors (84499368).

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

51999456 is a wasteful number, since it uses less digits than its factorization.

51999456 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 541674 (or 541666 counting only the distinct ones).

The product of its digits is 437400, while the sum is 48.

The square root of 51999456 is about 7211.0648312160. The cubic root of 51999456 is about 373.2498140836.

The spelling of 51999456 in words is "fifty-one million, nine hundred ninety-nine thousand, four hundred fifty-six".