51990456 has 64 divisors (see below), whose sum is σ = 151372800. Its totient is φ = 14571648.

The previous prime is 51990431. The next prime is 51990461. The reversal of 51990456 is 65409915.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5985 + ... + 11823.

It is an arithmetic number, because the mean of its divisors is an integer number (2365200).

Almost surely, 2^51990456 is an apocalyptic number.

51990456 is a gapful number since it is divisible by the number (56) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 51990456, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (75686400).

51990456 is an abundant number, since it is smaller than the sum of its proper divisors (99382344).

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

51990456 is a wasteful number, since it uses less digits than its factorization.

51990456 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5908 (or 5904 counting only the distinct ones).

The product of its (nonzero) digits is 48600, while the sum is 39.

The square root of 51990456 is about 7210.4407632266. The cubic root of 51990456 is about 373.2282789727.

The spelling of 51990456 in words is "fifty-one million, nine hundred ninety thousand, four hundred fifty-six".