72227757561 has 4 divisors (see below), whose sum is σ = 96303676752. Its totient is φ = 48151838372.

The previous prime is 72227757457. The next prime is 72227757619. The reversal of 72227757561 is 16575772227.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 72227757561 - 2²² = 72223563257 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (72227757061) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12037959591 + ... + 12037959596.

It is an arithmetic number, because the mean of its divisors is an integer number (24075919188).

Almost surely, 2^72227757561 is an apocalyptic number.

It is an amenable number.

72227757561 is a deficient number, since it is larger than the sum of its proper divisors (24075919191).

72227757561 is a wasteful number, since it uses less digits than its factorization.

72227757561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24075919190.

The product of its digits is 2881200, while the sum is 51.

The spelling of 72227757561 in words is "seventy-two billion, two hundred twenty-seven million, seven hundred fifty-seven thousand, five hundred sixty-one".