51513601613 has 2 divisors, whose sum is σ = 51513601614. Its totient is φ = 51513601612.

The previous prime is 51513601567. The next prime is 51513601673. The reversal of 51513601613 is 31610631515.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 51106288489 + 407313124 = 226067^2 + 20182^2 .

It is a cyclic number.

It is not a de Polignac number, because 51513601613 - 2⁶ = 51513601549 is a prime.

It is a super-2 number, since 2×51513601613² (a number of 22 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 51513601613.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51513601673) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25756800806 + 25756800807.

It is an arithmetic number, because the mean of its divisors is an integer number (25756800807).

Almost surely, 2^51513601613 is an apocalyptic number.

It is an amenable number.

51513601613 is a deficient number, since it is larger than the sum of its proper divisors (1).

51513601613 is an equidigital number, since it uses as much as digits as its factorization.

51513601613 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 8100, while the sum is 32.

The spelling of 51513601613 in words is "fifty-one billion, five hundred thirteen million, six hundred one thousand, six hundred thirteen".