72621636 has 12 divisors (see below), whose sum is σ = 169450512. Its totient is φ = 24207208.

The previous prime is 72621617. The next prime is 72621643. The reversal of 72621636 is 63612627.

It is a tau number, because it is divible by the number of its divisors (12).

It is a junction number, because it is equal to n+sod(n) for n = 72621597 and 72621606.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3025890 + ... + 3025913.

It is an arithmetic number, because the mean of its divisors is an integer number (14120876).

Almost surely, 2^72621636 is an apocalyptic number.

It is an amenable number.

72621636 is an abundant number, since it is smaller than the sum of its proper divisors (96828876).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

72621636 is a wasteful number, since it uses less digits than its factorization.

72621636 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6051810 (or 6051808 counting only the distinct ones).

The product of its digits is 18144, while the sum is 33.

The square root of 72621636 is about 8521.8329014362. The cubic root of 72621636 is about 417.2106084943.

Subtracting from 72621636 its reverse (63612627), we obtain a palindrome (9009009).

The spelling of 72621636 in words is "seventy-two million, six hundred twenty-one thousand, six hundred thirty-six".