51617991075 has 72 divisors (see below), whose sum is σ = 99162296064. Its totient is φ = 23209084800.

The previous prime is 51617991001. The next prime is 51617991077. The reversal of 51617991075 is 57019971615.

It is not a de Polignac number, because 51617991075 - 2⁹ = 51617990563 is a prime.

It is a Smith number, since the sum of its digits (51) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (51617991077) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 1940314 + ... + 1966736.

It is an arithmetic number, because the mean of its divisors is an integer number (1377254112).

Almost surely, 2^51617991075 is an apocalyptic number.

51617991075 is a deficient number, since it is larger than the sum of its proper divisors (47544304989).

51617991075 is a wasteful number, since it uses less digits than its factorization.

51617991075 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26565 (or 26499 counting only the distinct ones).

The product of its (nonzero) digits is 595350, while the sum is 51.

The spelling of 51617991075 in words is "fifty-one billion, six hundred seventeen million, nine hundred ninety-one thousand, seventy-five".