18713640 has 64 divisors (see below), whose sum is σ = 61248960. Its totient is φ = 4536320.

The previous prime is 18713633. The next prime is 18713647. The reversal of 18713640 is 4631781.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (18713633) and next prime (18713647).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 18713598 and 18713607.

It is not an unprimeable number, because it can be changed into a prime (18713647) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5769 + ... + 8408.

It is an arithmetic number, because the mean of its divisors is an integer number (957015).

Almost surely, 2^18713640 is an apocalyptic number.

18713640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18713640 is an abundant number, since it is smaller than the sum of its proper divisors (42535320).

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

18713640 is a wasteful number, since it uses less digits than its factorization.

18713640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14202 (or 14198 counting only the distinct ones).

The product of its (nonzero) digits is 4032, while the sum is 30.

The square root of 18713640 is about 4325.9264903602. The cubic root of 18713640 is about 265.4928055477.

The spelling of 18713640 in words is "eighteen million, seven hundred thirteen thousand, six hundred forty".