72521396 has 6 divisors (see below), whose sum is σ = 126912450. Its totient is φ = 36260696.

The previous prime is 72521387. The next prime is 72521401. The reversal of 72521396 is 69312527.

It can be written as a sum of positive squares in only one way, i.e., 58308496 + 14212900 = 7636^2 + 3770^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9065171 + ... + 9065178.

It is an arithmetic number, because the mean of its divisors is an integer number (21152075).

Almost surely, 2^72521396 is an apocalyptic number.

It is an amenable number.

72521396 is a deficient number, since it is larger than the sum of its proper divisors (54391054).

72521396 is a wasteful number, since it uses less digits than its factorization.

72521396 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18130353 (or 18130351 counting only the distinct ones).

The product of its digits is 22680, while the sum is 35.

The square root of 72521396 is about 8515.9495066610. The cubic root of 72521396 is about 417.0185608233.

The spelling of 72521396 in words is "seventy-two million, five hundred twenty-one thousand, three hundred ninety-six".