172390405 has 16 divisors (see below), whose sum is σ = 235488384. Its totient is φ = 119922880.

The previous prime is 172390399. The next prime is 172390423. The reversal of 172390405 is 504093271.

It is not a de Polignac number, because 172390405 - 2⁷ = 172390277 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 66874 + ... + 69403.

It is an arithmetic number, because the mean of its divisors is an integer number (14718024).

Almost surely, 2^172390405 is an apocalyptic number.

It is an amenable number.

172390405 is a deficient number, since it is larger than the sum of its proper divisors (63097979).

172390405 is a wasteful number, since it uses less digits than its factorization.

172390405 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 136316.

The product of its (nonzero) digits is 7560, while the sum is 31.

The square root of 172390405 is about 13129.7526633216. The cubic root of 172390405 is about 556.5502258434.

The spelling of 172390405 in words is "one hundred seventy-two million, three hundred ninety thousand, four hundred five".