73172531 has 2 divisors, whose sum is σ = 73172532. Its totient is φ = 73172530.

The previous prime is 73172527. The next prime is 73172549. The reversal of 73172531 is 13527137.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 73172531 - 2² = 73172527 is a prime.

It is a super-2 number, since 2×73172531² = 10708438585891922, which contains 22 as substring.

It is a Sophie Germain prime.

It is a junction number, because it is equal to n+sod(n) for n = 73172494 and 73172503.

It is not a weakly prime, because it can be changed into another prime (73172501) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36586265 + 36586266.

It is an arithmetic number, because the mean of its divisors is an integer number (36586266).

Almost surely, 2^73172531 is an apocalyptic number.

73172531 is a deficient number, since it is larger than the sum of its proper divisors (1).

73172531 is an equidigital number, since it uses as much as digits as its factorization.

73172531 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4410, while the sum is 29.

The square root of 73172531 is about 8554.0943997597. The cubic root of 73172531 is about 418.2629142732.

Adding to 73172531 its reverse (13527137), we get a palindrome (86699668).

The spelling of 73172531 in words is "seventy-three million, one hundred seventy-two thousand, five hundred thirty-one".