18923418 has 12 divisors (see below), whose sum is σ = 41000778. Its totient is φ = 6307800.

The previous prime is 18923407. The next prime is 18923441. The reversal of 18923418 is 81432981.

It can be written as a sum of positive squares in only one way, i.e., 9941409 + 8982009 = 3153^2 + 2997^2 .

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 525633 + ... + 525668.

Almost surely, 2^18923418 is an apocalyptic number.

18923418 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

18923418 is an abundant number, since it is smaller than the sum of its proper divisors (22077360).

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

18923418 is a wasteful number, since it uses less digits than its factorization.

18923418 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1051309 (or 1051306 counting only the distinct ones).

The product of its digits is 13824, while the sum is 36.

The square root of 18923418 is about 4350.1055159617. The cubic root of 18923418 is about 266.4811706498.

The spelling of 18923418 in words is "eighteen million, nine hundred twenty-three thousand, four hundred eighteen".