18415940 has 24 divisors (see below), whose sum is σ = 40709760. Its totient is φ = 6978528.

The previous prime is 18415933. The next prime is 18415967. The reversal of 18415940 is 4951481.

It is a junction number, because it is equal to n+sod(n) for n = 18415897 and 18415906.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 23852 + ... + 24611.

It is an arithmetic number, because the mean of its divisors is an integer number (1696240).

Almost surely, 2^18415940 is an apocalyptic number.

18415940 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18415940 is an abundant number, since it is smaller than the sum of its proper divisors (22293820).

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

18415940 is a wasteful number, since it uses less digits than its factorization.

18415940 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 48491 (or 48489 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 32.

The square root of 18415940 is about 4291.3797315083. The cubic root of 18415940 is about 264.0774374917.

The spelling of 18415940 in words is "eighteen million, four hundred fifteen thousand, nine hundred forty".