18021290 has 16 divisors (see below), whose sum is σ = 37072512. Its totient is φ = 6178704.

The previous prime is 18021287. The next prime is 18021301. The reversal of 18021290 is 9212081.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 128654 + ... + 128793.

It is an arithmetic number, because the mean of its divisors is an integer number (2317032).

Almost surely, 2^18021290 is an apocalyptic number.

18021290 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

18021290 is an abundant number, since it is smaller than the sum of its proper divisors (19051222).

18021290 is a wasteful number, since it uses less digits than its factorization.

18021290 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 257461.

The product of its (nonzero) digits is 288, while the sum is 23.

The square root of 18021290 is about 4245.1489962073. The cubic root of 18021290 is about 262.1774238668.

The spelling of 18021290 in words is "eighteen million, twenty-one thousand, two hundred ninety".