18738929664 has 896 divisors, whose sum is σ = 73395840000. Its totient is φ = 4682022912.

The previous prime is 18738929653. The next prime is 18738929689. The reversal of 18738929664 is 46692983781.

It is a tau number, because it is divible by the number of its divisors (896).

It is a super-2 number, since 2×18738929664² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 986259447 + ... + 986259465.

It is an arithmetic number, because the mean of its divisors is an integer number (81915000).

Almost surely, 2^18738929664 is an apocalyptic number.

18738929664 is a gapful number since it is divisible by the number (14) 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 18738929664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36697920000).

18738929664 is an abundant number, since it is smaller than the sum of its proper divisors (54656910336).

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

18738929664 is an equidigital number, since it uses as much as digits as its factorization.

18738929664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 88 (or 44 counting only the distinct ones).

The product of its digits is 31352832, while the sum is 63.

The spelling of 18738929664 in words is "eighteen billion, seven hundred thirty-eight million, nine hundred twenty-nine thousand, six hundred sixty-four".