51508369 has 8 divisors (see below), whose sum is σ = 56656800. Its totient is φ = 46824580.

The previous prime is 51508361. The next prime is 51508393. The reversal of 51508369 is 96380515.

It is not a de Polignac number, because 51508369 - 2³ = 51508361 is a prime.

It is a super-2 number, since 2×51508369² = 5306224154080322, which contains 22 as substring.

It is a hoax number, since the sum of its digits (37) coincides with the sum of the digits of its distinct prime factors.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51508361) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 18019 + ... + 20680.

It is an arithmetic number, because the mean of its divisors is an integer number (7082100).

Almost surely, 2^51508369 is an apocalyptic number.

It is an amenable number.

51508369 is a deficient number, since it is larger than the sum of its proper divisors (5148431).

51508369 is an equidigital number, since it uses as much as digits as its factorization.

51508369 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38732 (or 38710 counting only the distinct ones).

The product of its (nonzero) digits is 32400, while the sum is 37.

The square root of 51508369 is about 7176.9331193763. The cubic root of 51508369 is about 372.0710953067.

The spelling of 51508369 in words is "fifty-one million, five hundred eight thousand, three hundred sixty-nine".