72315644 has 6 divisors (see below), whose sum is σ = 126552384. Its totient is φ = 36157820.

The previous prime is 72315641. The next prime is 72315673. The reversal of 72315644 is 44651327.

It is a self number, because there is not a number n which added to its sum of digits gives 72315644.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72315641) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9039452 + ... + 9039459.

It is an arithmetic number, because the mean of its divisors is an integer number (21092064).

Almost surely, 2^72315644 is an apocalyptic number.

It is an amenable number.

72315644 is a deficient number, since it is larger than the sum of its proper divisors (54236740).

72315644 is a wasteful number, since it uses less digits than its factorization.

72315644 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18078915 (or 18078913 counting only the distinct ones).

The product of its digits is 20160, while the sum is 32.

The square root of 72315644 is about 8503.8605350746. The cubic root of 72315644 is about 416.6238098498.

The spelling of 72315644 in words is "seventy-two million, three hundred fifteen thousand, six hundred forty-four".