18613820 has 24 divisors (see below), whose sum is σ = 39330144. Its totient is φ = 7399616.

The previous prime is 18613817. The next prime is 18613867. The reversal of 18613820 is 2831681.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 554 + ... + 6126.

It is an arithmetic number, because the mean of its divisors is an integer number (1638756).

Almost surely, 2^18613820 is an apocalyptic number.

18613820 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18613820 is an abundant number, since it is smaller than the sum of its proper divisors (20716324).

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

18613820 is a wasteful number, since it uses less digits than its factorization.

18613820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5749 (or 5747 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 29.

The square root of 18613820 is about 4314.3736509487. The cubic root of 18613820 is about 265.0199106910.

The spelling of 18613820 in words is "eighteen million, six hundred thirteen thousand, eight hundred twenty".