72720643567 has 32 divisors (see below), whose sum is σ = 89965854720. Its totient is φ = 57789832320.

The previous prime is 72720643561. The next prime is 72720643573. The reversal of 72720643567 is 76534602727.

It is an interprime number because it is at equal distance from previous prime (72720643561) and next prime (72720643573).

It is not a de Polignac number, because 72720643567 - 2¹¹ = 72720641519 is a prime.

It is a Smith number, since the sum of its digits (49) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

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 72720643567.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72720643561) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 11834898 + ... + 11841040.

It is an arithmetic number, because the mean of its divisors is an integer number (2811432960).

Almost surely, 2^72720643567 is an apocalyptic number.

72720643567 is a deficient number, since it is larger than the sum of its proper divisors (17245211153).

72720643567 is a wasteful number, since it uses less digits than its factorization.

72720643567 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10543.

The product of its (nonzero) digits is 2963520, while the sum is 49.

The spelling of 72720643567 in words is "seventy-two billion, seven hundred twenty million, six hundred forty-three thousand, five hundred sixty-seven".