17920145 has 16 divisors (see below), whose sum is σ = 21954240. Its totient is φ = 14040000.

The previous prime is 17920117. The next prime is 17920163. The reversal of 17920145 is 54102971.

It is not a de Polignac number, because 17920145 - 2¹² = 17916049 is a prime.

It is a super-2 number, since 2×17920145² = 642263193642050, which contains 22 as substring.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 71270 + ... + 71520.

It is an arithmetic number, because the mean of its divisors is an integer number (1372140).

Almost surely, 2^17920145 is an apocalyptic number.

It is an amenable number.

17920145 is a deficient number, since it is larger than the sum of its proper divisors (4034095).

17920145 is a wasteful number, since it uses less digits than its factorization.

17920145 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 496.

The product of its (nonzero) digits is 2520, while the sum is 29.

The square root of 17920145 is about 4233.2192241839. The cubic root of 17920145 is about 261.6860106236.

It can be divided in two parts, 179 and 20145, that multiplied together give a triangular number (3605955 = T₂₆₈₅).

The spelling of 17920145 in words is "seventeen million, nine hundred twenty thousand, one hundred forty-five".