51807399 has 8 divisors (see below), whose sum is σ = 78944640. Its totient is φ = 29604216.

The previous prime is 51807397. The next prime is 51807419. The reversal of 51807399 is 99370815.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 51807399 - 2¹ = 51807397 is a prime.

It is a super-2 number, since 2×51807399² = 5368013182290402, 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 51807399.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51807397) 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, 1233489 + ... + 1233530.

It is an arithmetic number, because the mean of its divisors is an integer number (9868080).

Almost surely, 2^51807399 is an apocalyptic number.

51807399 is a deficient number, since it is larger than the sum of its proper divisors (27137241).

51807399 is a wasteful number, since it uses less digits than its factorization.

51807399 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2467029.

The product of its (nonzero) digits is 68040, while the sum is 42.

The square root of 51807399 is about 7197.7356856167. The cubic root of 51807399 is about 372.7897216024.

The spelling of 51807399 in words is "fifty-one million, eight hundred seven thousand, three hundred ninety-nine".