18940040 has 128 divisors (see below), whose sum is σ = 54120960. Its totient is φ = 5812224.

The previous prime is 18940037. The next prime is 18940067. The reversal of 18940040 is 4004981.

It is a junction number, because it is equal to n+sod(n) for n = 18939991 and 18940009.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 109394 + ... + 109566.

It is an arithmetic number, because the mean of its divisors is an integer number (422820).

Almost surely, 2^18940040 is an apocalyptic number.

18940040 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18940040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27060480).

18940040 is an abundant number, since it is smaller than the sum of its proper divisors (35180920).

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

18940040 is a wasteful number, since it uses less digits than its factorization.

18940040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 231 (or 227 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 26.

The square root of 18940040 is about 4352.0156249720. The cubic root of 18940040 is about 266.5591719519.

The spelling of 18940040 in words is "eighteen million, nine hundred forty thousand, forty".