18947240 has 64 divisors (see below), whose sum is σ = 46569600. Its totient is φ = 6895872.

The previous prime is 18947213. The next prime is 18947311. The reversal of 18947240 is 4274981.

It is a self number, because there is not a number n which added to its sum of digits gives 18947240.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 42941 + ... + 43379.

It is an arithmetic number, because the mean of its divisors is an integer number (727650).

Almost surely, 2^18947240 is an apocalyptic number.

18947240 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 18947240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23284800).

18947240 is an abundant number, since it is smaller than the sum of its proper divisors (27622360).

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

18947240 is a wasteful number, since it uses less digits than its factorization.

18947240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 546 (or 542 counting only the distinct ones).

The product of its (nonzero) digits is 16128, while the sum is 35.

The square root of 18947240 is about 4352.8427492847. The cubic root of 18947240 is about 266.5929448988.

The spelling of 18947240 in words is "eighteen million, nine hundred forty-seven thousand, two hundred forty".