18368890 has 32 divisors (see below), whose sum is σ = 34609680. Its totient is φ = 7010304.

The previous prime is 18368887. The next prime is 18368923. The reversal of 18368890 is 9886381.

18368890 = T₁₁₁₁ + T₁₁₁₂ + ... + T₁₁₃₉.

It is a happy number.

It can be written as a sum of positive squares in 8 ways, for example, as 5184729 + 13184161 = 2277^2 + 3631^2 .

It is a super-2 number, since 2×18368890² = 674832239664200, which contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 27804 + ... + 28456.

Almost surely, 2^18368890 is an apocalyptic number.

18368890 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

18368890 is a deficient number, since it is larger than the sum of its proper divisors (16240790).

18368890 is a wasteful number, since it uses less digits than its factorization.

18368890 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 786.

The product of its (nonzero) digits is 82944, while the sum is 43.

The square root of 18368890 is about 4285.8943057430. The cubic root of 18368890 is about 263.8523527790.

The spelling of 18368890 in words is "eighteen million, three hundred sixty-eight thousand, eight hundred ninety".