18621164640 has 384 divisors, whose sum is σ = 66023838720. Its totient is φ = 4380991488.

The previous prime is 18621164609. The next prime is 18621164647. The reversal of 18621164640 is 4646112681.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18621164647) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 13621237 + ... + 13622603.

It is an arithmetic number, because the mean of its divisors is an integer number (171937080).

Almost surely, 2^18621164640 is an apocalyptic number.

18621164640 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 18621164640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33011919360).

18621164640 is an abundant number, since it is smaller than the sum of its proper divisors (47402674080).

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

18621164640 is a wasteful number, since it uses less digits than its factorization.

18621164640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1494 (or 1486 counting only the distinct ones).

The product of its (nonzero) digits is 55296, while the sum is 39.

The spelling of 18621164640 in words is "eighteen billion, six hundred twenty-one million, one hundred sixty-four thousand, six hundred forty".