18722340 has 240 divisors, whose sum is σ = 72855552. Its totient is φ = 3919104.

The previous prime is 18722323. The next prime is 18722359. The reversal of 18722340 is 4322781.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is an unprimeable number.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 147357 + ... + 147483.

Almost surely, 2^18722340 is an apocalyptic number.

18722340 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 18722340, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36427776).

18722340 is an abundant number, since it is smaller than the sum of its proper divisors (54133212).

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

18722340 is a wasteful number, since it uses less digits than its factorization.

18722340 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 168 (or 157 counting only the distinct ones).

The product of its (nonzero) digits is 2688, while the sum is 27.

The square root of 18722340 is about 4326.9319384525. The cubic root of 18722340 is about 265.5339418447.

The spelling of 18722340 in words is "eighteen million, seven hundred twenty-two thousand, three hundred forty".