18406390 has 16 divisors (see below), whose sum is σ = 34027632. Its totient is φ = 7163424.

The previous prime is 18406379. The next prime is 18406471. The reversal of 18406390 is 9360481.

It is a congruent number.

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, 24504 + ... + 25243.

It is an arithmetic number, because the mean of its divisors is an integer number (2126727).

Almost surely, 2^18406390 is an apocalyptic number.

18406390 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

18406390 is a deficient number, since it is larger than the sum of its proper divisors (15621242).

18406390 is a wasteful number, since it uses less digits than its factorization.

18406390 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 49791.

The product of its (nonzero) digits is 5184, while the sum is 31.

The square root of 18406390 is about 4290.2668914649. The cubic root of 18406390 is about 264.0317818334.

The spelling of 18406390 in words is "eighteen million, four hundred six thousand, three hundred ninety".