51617320 has 16 divisors (see below), whose sum is σ = 116139060. Its totient is φ = 20646912.

The previous prime is 51617311. The next prime is 51617333. The reversal of 51617320 is 2371615.

It can be written as a sum of positive squares in 2 ways, for example, as 51523684 + 93636 = 7178^2 + 306^2 .

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, 645177 + ... + 645256.

Almost surely, 2^51617320 is an apocalyptic number.

It is an amenable number.

51617320 is an abundant number, since it is smaller than the sum of its proper divisors (64521740).

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

51617320 is a wasteful number, since it uses less digits than its factorization.

51617320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1290444 (or 1290440 counting only the distinct ones).

The product of its (nonzero) digits is 1260, while the sum is 25.

The square root of 51617320 is about 7184.5194689694. The cubic root of 51617320 is about 372.3332466842. Note that the first 3 decimals are identical.

Adding to 51617320 its reverse (2371615), we get a palindrome (53988935).

The spelling of 51617320 in words is "fifty-one million, six hundred seventeen thousand, three hundred twenty".