72321523 has 4 divisors (see below), whose sum is σ = 73340208. Its totient is φ = 71302840.

The previous prime is 72321517. The next prime is 72321527. The reversal of 72321523 is 32512327.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 72321523 - 2¹³ = 72313331 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (72321527) 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, 509236 + ... + 509377.

It is an arithmetic number, because the mean of its divisors is an integer number (18335052).

Almost surely, 2^72321523 is an apocalyptic number.

72321523 is a deficient number, since it is larger than the sum of its proper divisors (1018685).

72321523 is a wasteful number, since it uses less digits than its factorization.

72321523 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1018684.

The product of its digits is 2520, while the sum is 25.

The square root of 72321523 is about 8504.2061945839. The cubic root of 72321523 is about 416.6350995463.

The spelling of 72321523 in words is "seventy-two million, three hundred twenty-one thousand, five hundred twenty-three".