81659300631 has 8 divisors (see below), whose sum is σ = 108884494320. Its totient is φ = 54436820352.

The previous prime is 81659300621. The next prime is 81659300677. The reversal of 81659300631 is 13600395618.

It is a happy number.

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

It is not a de Polignac number, because 81659300631 - 2¹⁹ = 81658776343 is a prime.

It is a super-2 number, since 2×81659300631² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81659300621) 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, 607060 + ... + 729273.

It is an arithmetic number, because the mean of its divisors is an integer number (13610561790).

Almost surely, 2^81659300631 is an apocalyptic number.

81659300631 is a deficient number, since it is larger than the sum of its proper divisors (27225193689).

81659300631 is a wasteful number, since it uses less digits than its factorization.

81659300631 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1356705.

The product of its (nonzero) digits is 116640, while the sum is 42.

The spelling of 81659300631 in words is "eighty-one billion, six hundred fifty-nine million, three hundred thousand, six hundred thirty-one".