18867940 has 72 divisors (see below), whose sum is σ = 49670712. Its totient is φ = 5967360.

The previous prime is 18867923. The next prime is 18867967. The reversal of 18867940 is 4976881.

It can be written as a sum of positive squares in 4 ways, for example, as 153664 + 18714276 = 392^2 + 4326^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 12000 + ... + 13480.

It is an arithmetic number, because the mean of its divisors is an integer number (689871).

Almost surely, 2^18867940 is an apocalyptic number.

18867940 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 18867940, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24835356).

18867940 is an abundant number, since it is smaller than the sum of its proper divisors (30802772).

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

18867940 is a wasteful number, since it uses less digits than its factorization.

18867940 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1517 (or 1508 counting only the distinct ones).

The product of its (nonzero) digits is 96768, while the sum is 43.

The square root of 18867940 is about 4343.7242085565. The cubic root of 18867940 is about 266.2205004530.

The spelling of 18867940 in words is "eighteen million, eight hundred sixty-seven thousand, nine hundred forty".