51691655619615 has 64 divisors (see below), whose sum is σ = 93362309475840. Its totient is φ = 24191742005760.

The previous prime is 51691655619599. The next prime is 51691655619629.

51691655619615 is nontrivially palindromic in base 10.

51691655619615 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 51691655619615 - 2⁴ = 51691655619599 is a prime.

It is a congruent number.

It is an unprimeable number.

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 in 63 ways as a sum of consecutive naturals, for example, 15949069 + ... + 18914441.

It is an arithmetic number, because the mean of its divisors is an integer number (1458786085560).

Almost surely, 2^{51691655619615} is an apocalyptic number.

51691655619615 is a gapful number since it is divisible by the number (55) formed by its first and last digit.

51691655619615 is a deficient number, since it is larger than the sum of its proper divisors (41670653856225).

51691655619615 is a wasteful number, since it uses less digits than its factorization.

51691655619615 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2969064.

The product of its digits is 65610000, while the sum is 66.

The spelling of 51691655619615 in words is "fifty-one trillion, six hundred ninety-one billion, six hundred fifty-five million, six hundred nineteen thousand, six hundred fifteen".