51057216 has 252 divisors, whose sum is σ = 179179728. Its totient is φ = 14370048.

The previous prime is 51057191. The next prime is 51057221. The reversal of 51057216 is 61275015.

It is a tau number, because it is divible by the number of its divisors (252).

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a self number, because there is not a number n which added to its sum of digits gives 51057216.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 762015 + ... + 762081.

Almost surely, 2^51057216 is an apocalyptic number.

51057216 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 51057216, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (89589864).

51057216 is an abundant number, since it is smaller than the sum of its proper divisors (128122512).

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

51057216 is an equidigital number, since it uses as much as digits as its factorization.

51057216 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 108 (or 79 counting only the distinct ones).

The product of its (nonzero) digits is 2100, while the sum is 27.

The square root of 51057216 is about 7145.4332268939. The cubic root of 51057216 is about 370.9816058283.

It can be divided in two parts, 5105 and 7216, that added together give a palindrome (12321).

The spelling of 51057216 in words is "fifty-one million, fifty-seven thousand, two hundred sixteen".