72164068581 has 12 divisors (see below), whose sum is σ = 105761114816. Its totient is φ = 43735798920.

The previous prime is 72164068541. The next prime is 72164068583. The reversal of 72164068581 is 18586046127.

It is not a de Polignac number, because 72164068581 - 2⁹ = 72164068069 is a prime.

It is a super-2 number, since 2×72164068581² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 72164068581.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72164068583) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 99399181 + ... + 99399906.

Almost surely, 2^72164068581 is an apocalyptic number.

It is an amenable number.

72164068581 is a deficient number, since it is larger than the sum of its proper divisors (33597046235).

72164068581 is a wasteful number, since it uses less digits than its factorization.

72164068581 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 198799112 (or 198799101 counting only the distinct ones).

The product of its (nonzero) digits is 645120, while the sum is 48.

The spelling of 72164068581 in words is "seventy-two billion, one hundred sixty-four million, sixty-eight thousand, five hundred eighty-one".