72640822617 has 18 divisors (see below), whose sum is σ = 115331482266. Its totient is φ = 44024740320.

The previous prime is 72640822609. The next prime is 72640822711. The reversal of 72640822617 is 71622804627.

It is a happy number.

72640822617 is a `hidden beast` number, since 7 + 2 + 6 + 4 + 0 + 8 + 22 + 617 = 666.

It can be written as a sum of positive squares in only one way, i.e., 58862523456 + 13778299161 = 242616^2 + 117381^2 .

It is not a de Polignac number, because 72640822617 - 2³ = 72640822609 is a prime.

It is a super-2 number, since 2×72640822617² (a number of 23 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (72640822607) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 33350988 + ... + 33353165.

Almost surely, 2^72640822617 is an apocalyptic number.

It is an amenable number.

72640822617 is a deficient number, since it is larger than the sum of its proper divisors (42690659649).

72640822617 is a wasteful number, since it uses less digits than its factorization.

72640822617 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 66704181 (or 66704167 counting only the distinct ones).

The product of its (nonzero) digits is 451584, while the sum is 45.

The spelling of 72640822617 in words is "seventy-two billion, six hundred forty million, eight hundred twenty-two thousand, six hundred seventeen".