18394940 has 24 divisors (see below), whose sum is σ = 40309920. Its totient is φ = 7037888.

The previous prime is 18394933. The next prime is 18394951. The reversal of 18394940 is 4949381.

It is a junction number, because it is equal to n+sod(n) for n = 18394894 and 18394903.

It is a congruent number.

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 7 ways as a sum of consecutive naturals, for example, 19535 + ... + 20454.

It is an arithmetic number, because the mean of its divisors is an integer number (1679580).

Almost surely, 2^18394940 is an apocalyptic number.

18394940 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18394940 is an abundant number, since it is smaller than the sum of its proper divisors (21914980).

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

18394940 is a wasteful number, since it uses less digits than its factorization.

18394940 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40021 (or 40019 counting only the distinct ones).

The product of its (nonzero) digits is 31104, while the sum is 38.

The square root of 18394940 is about 4288.9322680593. The cubic root of 18394940 is about 263.9770220283.

The spelling of 18394940 in words is "eighteen million, three hundred ninety-four thousand, nine hundred forty".