18722620 has 24 divisors (see below), whose sum is σ = 44934624. Its totient is φ = 6419136.

The previous prime is 18722617. The next prime is 18722623. The reversal of 18722620 is 2622781.

It is an interprime number because it is at equal distance from previous prime (18722617) and next prime (18722623).

It is a Harshad number since it is a multiple of its sum of digits (28).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18722623) 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, 66727 + ... + 67006.

It is an arithmetic number, because the mean of its divisors is an integer number (1872276).

Almost surely, 2^18722620 is an apocalyptic number.

18722620 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18722620 is an abundant number, since it is smaller than the sum of its proper divisors (26212004).

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

18722620 is a wasteful number, since it uses less digits than its factorization.

18722620 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 133749 (or 133747 counting only the distinct ones).

The product of its (nonzero) digits is 2688, while the sum is 28.

The square root of 18722620 is about 4326.9642938208. The cubic root of 18722620 is about 265.5352655598.

The spelling of 18722620 in words is "eighteen million, seven hundred twenty-two thousand, six hundred twenty".