18523240 has 32 divisors (see below), whose sum is σ = 41801760. Its totient is φ = 7387200.

The previous prime is 18523231. The next prime is 18523243. The reversal of 18523240 is 4232581.

It is a super-2 number, since 2×18523240² = 686220840195200, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (18523243) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 22435 + ... + 23245.

It is an arithmetic number, because the mean of its divisors is an integer number (1306305).

Almost surely, 2^18523240 is an apocalyptic number.

18523240 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18523240 is an abundant number, since it is smaller than the sum of its proper divisors (23278520).

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

18523240 is a wasteful number, since it uses less digits than its factorization.

18523240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1393 (or 1389 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 25.

The square root of 18523240 is about 4303.8633807313. The cubic root of 18523240 is about 264.5893247381.

The spelling of 18523240 in words is "eighteen million, five hundred twenty-three thousand, two hundred forty".