17990145 has 12 divisors (see below), whose sum is σ = 31182996. Its totient is φ = 9594720.

The previous prime is 17990113. The next prime is 17990149. The reversal of 17990145 is 54109971.

It can be written as a sum of positive squares in 2 ways, for example, as 9884736 + 8105409 = 3144^2 + 2847^2 .

It is not a de Polignac number, because 17990145 - 2⁵ = 17990113 is a prime.

It is not an unprimeable number, because it can be changed into a prime (17990149) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 199846 + ... + 199935.

It is an arithmetic number, because the mean of its divisors is an integer number (2598583).

Almost surely, 2^17990145 is an apocalyptic number.

17990145 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

17990145 is a deficient number, since it is larger than the sum of its proper divisors (13192851).

17990145 is a wasteful number, since it uses less digits than its factorization.

17990145 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 399792 (or 399789 counting only the distinct ones).

The product of its (nonzero) digits is 11340, while the sum is 36.

The square root of 17990145 is about 4241.4791052179. The cubic root of 17990145 is about 262.0263021591.

The spelling of 17990145 in words is "seventeen million, nine hundred ninety thousand, one hundred forty-five".