18990620 has 48 divisors (see below), whose sum is σ = 44700768. Its totient is φ = 6716160.

The previous prime is 18990619. The next prime is 18990623. The reversal of 18990620 is 2609981.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18990623) 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, 6974 + ... + 9306.

It is an arithmetic number, because the mean of its divisors is an integer number (931266).

Almost surely, 2^18990620 is an apocalyptic number.

18990620 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 18990620, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22350384).

18990620 is an abundant number, since it is smaller than the sum of its proper divisors (25710148).

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

18990620 is a wasteful number, since it uses less digits than its factorization.

18990620 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2390 (or 2388 counting only the distinct ones).

The product of its (nonzero) digits is 7776, while the sum is 35.

The square root of 18990620 is about 4357.8228509199. The cubic root of 18990620 is about 266.7962460520.

It can be divided in two parts, 189 and 90620, that added together give a palindrome (90809).

The spelling of 18990620 in words is "eighteen million, nine hundred ninety thousand, six hundred twenty".