72687621 has 4 divisors (see below), whose sum is σ = 96916832. Its totient is φ = 48458412.

The previous prime is 72687611. The next prime is 72687649. The reversal of 72687621 is 12678627.

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 not a de Polignac number, because 72687621 - 2⁷ = 72687493 is a prime.

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 72687621.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72687611) 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, 12114601 + ... + 12114606.

It is an arithmetic number, because the mean of its divisors is an integer number (24229208).

Almost surely, 2^72687621 is an apocalyptic number.

It is an amenable number.

72687621 is a deficient number, since it is larger than the sum of its proper divisors (24229211).

72687621 is a wasteful number, since it uses less digits than its factorization.

72687621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24229210.

The product of its digits is 56448, while the sum is 39.

The square root of 72687621 is about 8525.7035486815. The cubic root of 72687621 is about 417.3369313084.

The spelling of 72687621 in words is "seventy-two million, six hundred eighty-seven thousand, six hundred twenty-one".