51639795 has 32 divisors (see below), whose sum is σ = 97208640. Its totient is φ = 25920000.

The previous prime is 51639743. The next prime is 51639803. The reversal of 51639795 is 59793615.

51639795 is a `hidden beast` number, since 5 + 1 + 639 + 7 + 9 + 5 = 666.

It is not a de Polignac number, because 51639795 - 2⁷ = 51639667 is a prime.

It is a super-4 number, since 4×51639795⁴ (a number of 32 digits) contains 4444 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 51639795.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 8956 + ... + 13545.

It is an arithmetic number, because the mean of its divisors is an integer number (3037770).

Almost surely, 2^51639795 is an apocalyptic number.

51639795 is a deficient number, since it is larger than the sum of its proper divisors (45568845).

51639795 is a wasteful number, since it uses less digits than its factorization.

51639795 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22532 (or 22526 counting only the distinct ones).

The product of its digits is 255150, while the sum is 45.

The square root of 51639795 is about 7186.0834256221. The cubic root of 51639795 is about 372.3872787770.

The spelling of 51639795 in words is "fifty-one million, six hundred thirty-nine thousand, seven hundred ninety-five".