51639727 has 4 divisors (see below), whose sum is σ = 54677376. Its totient is φ = 48602080.

The previous prime is 51639719. The next prime is 51639737. The reversal of 51639727 is 72793615.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 51639727 - 2³ = 51639719 is a prime.

It is a super-2 number, since 2×51639727² = 5333322809269058, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 51639727.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51639737) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 1518799 + ... + 1518832.

It is an arithmetic number, because the mean of its divisors is an integer number (13669344).

Almost surely, 2^51639727 is an apocalyptic number.

51639727 is a deficient number, since it is larger than the sum of its proper divisors (3037649).

51639727 is a wasteful number, since it uses less digits than its factorization.

51639727 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3037648.

The product of its digits is 79380, while the sum is 40.

The square root of 51639727 is about 7186.0786942532. The cubic root of 51639727 is about 372.3871153220.

The spelling of 51639727 in words is "fifty-one million, six hundred thirty-nine thousand, seven hundred twenty-seven".