72172501 has 4 divisors (see below), whose sum is σ = 72273600. Its totient is φ = 72071404.

The previous prime is 72172493. The next prime is 72172519. The reversal of 72172501 is 10527127.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 10527127 = 13 ⋅809779.

It is a cyclic number.

It is not a de Polignac number, because 72172501 - 2³ = 72172493 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72172571) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 49471 + ... + 50908.

It is an arithmetic number, because the mean of its divisors is an integer number (18068400).

Almost surely, 2^72172501 is an apocalyptic number.

It is an amenable number.

72172501 is a deficient number, since it is larger than the sum of its proper divisors (101099).

72172501 is a wasteful number, since it uses less digits than its factorization.

72172501 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 101098.

The product of its (nonzero) digits is 980, while the sum is 25.

The square root of 72172501 is about 8495.4400121477. The cubic root of 72172501 is about 416.3487371695.

Adding to 72172501 its reverse (10527127), we get a palindrome (82699628).

The spelling of 72172501 in words is "seventy-two million, one hundred seventy-two thousand, five hundred one".