18644239152 has 280 divisors, whose sum is σ = 67527463680. Its totient is φ = 4842426240.

The previous prime is 18644239073. The next prime is 18644239177. The reversal of 18644239152 is 25193244681.

18644239152 is a `hidden beast` number, since 18 + 64 + 423 + 9 + 152 = 666.

It is a junction number, because it is equal to n+sod(n) for n = 18644239098 and 18644239107.

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 55 ways as a sum of consecutive naturals, for example, 887749 + ... + 908507.

Almost surely, 2^18644239152 is an apocalyptic number.

18644239152 is a gapful number since it is divisible by the number (12) 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 18644239152, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33763731840).

18644239152 is an abundant number, since it is smaller than the sum of its proper divisors (48883224528).

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

18644239152 is a wasteful number, since it uses less digits than its factorization.

18644239152 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20803 (or 20782 counting only the distinct ones).

The product of its digits is 414720, while the sum is 45.

The spelling of 18644239152 in words is "eighteen billion, six hundred forty-four million, two hundred thirty-nine thousand, one hundred fifty-two".