72521031 has 32 divisors (see below), whose sum is σ = 112347648. Its totient is φ = 41123840.

The previous prime is 72521023. The next prime is 72521051. The reversal of 72521031 is 13012527.

It is a cyclic number.

It is not a de Polignac number, because 72521031 - 2³ = 72521023 is a prime.

It is a super-2 number, since 2×72521031² = 10518599874605922, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 72520989 and 72521007.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72521011) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 143926 + ... + 144428.

It is an arithmetic number, because the mean of its divisors is an integer number (3510864).

Almost surely, 2^72521031 is an apocalyptic number.

72521031 is a deficient number, since it is larger than the sum of its proper divisors (39826617).

72521031 is a wasteful number, since it uses less digits than its factorization.

72521031 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 791.

The product of its (nonzero) digits is 420, while the sum is 21.

The square root of 72521031 is about 8515.9280762580. The cubic root of 72521031 is about 417.0178612044.

Adding to 72521031 its reverse (13012527), we get a palindrome (85533558).

The spelling of 72521031 in words is "seventy-two million, five hundred twenty-one thousand, thirty-one".