172890531 has 40 divisors (see below), whose sum is σ = 286456368. Its totient is φ = 103032000.

The previous prime is 172890457. The next prime is 172890539. The reversal of 172890531 is 135098271.

172890531 is a `hidden beast` number, since 17 + 28 + 90 + 531 = 666.

It is not a de Polignac number, because 172890531 - 2⁹ = 172890019 is a prime.

It is a super-2 number, since 2×172890531² = 59782271418923922, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (172890539) 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 39 ways as a sum of consecutive naturals, for example, 52761 + ... + 55941.

Almost surely, 2^172890531 is an apocalyptic number.

172890531 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

172890531 is a deficient number, since it is larger than the sum of its proper divisors (113565837).

172890531 is a wasteful number, since it uses less digits than its factorization.

172890531 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3265 (or 3256 counting only the distinct ones).

The product of its (nonzero) digits is 15120, while the sum is 36.

The square root of 172890531 is about 13148.7843924828. The cubic root of 172890531 is about 557.0879133476.

The spelling of 172890531 in words is "one hundred seventy-two million, eight hundred ninety thousand, five hundred thirty-one".