51697118591 has 8 divisors (see below), whose sum is σ = 52760451600. Its totient is φ = 50640022720.

The previous prime is 51697118579. The next prime is 51697118623. The reversal of 51697118591 is 19581179615.

It is a happy number.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-51697118591 is a prime.

It is a super-2 number, since 2×51697118591² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51697118491) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1542536 + ... + 1575693.

It is an arithmetic number, because the mean of its divisors is an integer number (6595056450).

Almost surely, 2^51697118591 is an apocalyptic number.

51697118591 is a deficient number, since it is larger than the sum of its proper divisors (1063333009).

51697118591 is a wasteful number, since it uses less digits than its factorization.

51697118591 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3118569.

The product of its digits is 680400, while the sum is 53.

The spelling of 51697118591 in words is "fifty-one billion, six hundred ninety-seven million, one hundred eighteen thousand, five hundred ninety-one".