18945290 has 64 divisors (see below), whose sum is σ = 42577920. Its totient is φ = 5909760.

The previous prime is 18945287. The next prime is 18945317. The reversal of 18945290 is 9254981.

18945290 = 21² + 22² + ... + 384².

It is an alternating number because its digits alternate between odd and even.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 99095 + ... + 99285.

It is an arithmetic number, because the mean of its divisors is an integer number (665280).

Almost surely, 2^18945290 is an apocalyptic number.

18945290 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

18945290 is an abundant number, since it is smaller than the sum of its proper divisors (23632630).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

18945290 is a wasteful number, since it uses less digits than its factorization.

18945290 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 327.

The product of its (nonzero) digits is 25920, while the sum is 38.

The square root of 18945290 is about 4352.6187519699. The cubic root of 18945290 is about 266.5837989039.

The spelling of 18945290 in words is "eighteen million, nine hundred forty-five thousand, two hundred ninety".