18257121792 has 640 divisors, whose sum is σ = 69515550720. Its totient is φ = 4598415360.

The previous prime is 18257121781. The next prime is 18257121811. The reversal of 18257121792 is 29712175281.

18257121792 is a `hidden beast` number, since 1 + 8 + 2 + 571 + 2 + 1 + 79 + 2 = 666.

It is a super-4 number, since 4×18257121792⁴ (a number of 42 digits) contains 4444 as substring. Note that it is a super-d number also for d = 2.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 28933317 + ... + 28933947.

It is an arithmetic number, because the mean of its divisors is an integer number (108618048).

Almost surely, 2^18257121792 is an apocalyptic number.

18257121792 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 18257121792, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34757775360).

18257121792 is an abundant number, since it is smaller than the sum of its proper divisors (51258428928).

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

18257121792 is a wasteful number, since it uses less digits than its factorization.

18257121792 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 701 (or 679 counting only the distinct ones).

The product of its digits is 141120, while the sum is 45.

The spelling of 18257121792 in words is "eighteen billion, two hundred fifty-seven million, one hundred twenty-one thousand, seven hundred ninety-two".