18355138 has 16 divisors (see below), whose sum is σ = 29251584. Its totient is φ = 8608320.

The previous prime is 18355111. The next prime is 18355151. The reversal of 18355138 is 83155381.

It is a super-2 number, since 2×18355138² = 673822181998088, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (34).

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, 11743 + ... + 13213.

It is an arithmetic number, because the mean of its divisors is an integer number (1828224).

Almost surely, 2^18355138 is an apocalyptic number.

18355138 is a deficient number, since it is larger than the sum of its proper divisors (10896446).

18355138 is a wasteful number, since it uses less digits than its factorization.

18355138 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1857.

The product of its digits is 14400, while the sum is 34.

The square root of 18355138 is about 4284.2896727462. The cubic root of 18355138 is about 263.7864913609.

The spelling of 18355138 in words is "eighteen million, three hundred fifty-five thousand, one hundred thirty-eight".