51257220 has 48 divisors (see below), whose sum is σ = 164024448. Its totient is φ = 11715840.

The previous prime is 51257189. The next prime is 51257249. The reversal of 51257220 is 2275215.

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, 60601 + ... + 61440.

It is an arithmetic number, because the mean of its divisors is an integer number (3417176).

Almost surely, 2^51257220 is an apocalyptic number.

It is an amenable number.

51257220 is an abundant number, since it is smaller than the sum of its proper divisors (112767228).

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

51257220 is a wasteful number, since it uses less digits than its factorization.

51257220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 122060 (or 122058 counting only the distinct ones).

The product of its (nonzero) digits is 1400, while the sum is 24.

The square root of 51257220 is about 7159.4147805529. The cubic root of 51257220 is about 371.4653842071.

The spelling of 51257220 in words is "fifty-one million, two hundred fifty-seven thousand, two hundred twenty".