51639955 has 8 divisors (see below), whose sum is σ = 63967104. Its totient is φ = 39979200.

The previous prime is 51639919. The next prime is 51639961. The reversal of 51639955 is 55993615.

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

It is not a de Polignac number, because 51639955 - 2⁹ = 51639443 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 166426 + ... + 166735.

It is an arithmetic number, because the mean of its divisors is an integer number (7995888).

Almost surely, 2^51639955 is an apocalyptic number.

51639955 is a deficient number, since it is larger than the sum of its proper divisors (12327149).

51639955 is a wasteful number, since it uses less digits than its factorization.

51639955 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 333197.

The product of its digits is 182250, while the sum is 43.

The square root of 51639955 is about 7186.0945582423. The cubic root of 51639955 is about 372.3876633764.

The spelling of 51639955 in words is "fifty-one million, six hundred thirty-nine thousand, nine hundred fifty-five".