51220456 has 64 divisors (see below), whose sum is σ = 117262080. Its totient is φ = 20474880.

The previous prime is 51220427. The next prime is 51220457. The reversal of 51220456 is 65402215.

It is a super-2 number, since 2×51220456² = 5247070225695872, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 51220456.

It is not an unprimeable number, because it can be changed into a prime (51220457) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 164541 + ... + 164851.

It is an arithmetic number, because the mean of its divisors is an integer number (1832220).

Almost surely, 2^51220456 is an apocalyptic number.

51220456 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 51220456, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (58631040).

51220456 is an abundant number, since it is smaller than the sum of its proper divisors (66041624).

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

51220456 is a wasteful number, since it uses less digits than its factorization.

51220456 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 514 (or 510 counting only the distinct ones).

The product of its (nonzero) digits is 2400, while the sum is 25.

The square root of 51220456 is about 7156.8467917093. The cubic root of 51220456 is about 371.3765523656.

The spelling of 51220456 in words is "fifty-one million, two hundred twenty thousand, four hundred fifty-six".