172906731 has 20 divisors (see below), whose sum is σ = 258649600. Its totient is φ = 115112016.

The previous prime is 172906697. The next prime is 172906733. The reversal of 172906731 is 137609271.

It is a happy number.

It is not a de Polignac number, because 172906731 - 2¹⁸ = 172644587 is a prime.

It is a super-2 number, since 2×172906731² = 59793475250212722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (172906733) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 102765 + ... + 104433.

It is an arithmetic number, because the mean of its divisors is an integer number (12932480).

Almost surely, 2^172906731 is an apocalyptic number.

172906731 is a deficient number, since it is larger than the sum of its proper divisors (85742869).

172906731 is a wasteful number, since it uses less digits than its factorization.

172906731 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2960 (or 2951 counting only the distinct ones).

The product of its (nonzero) digits is 15876, while the sum is 36.

The square root of 172906731 is about 13149.4004045812. The cubic root of 172906731 is about 557.1053126856.

The spelling of 172906731 in words is "one hundred seventy-two million, nine hundred six thousand, seven hundred thirty-one".