18816521201280 has 2560 divisors, whose sum is σ = 80485163827200. Its totient is φ = 4173061939200.

The previous prime is 18816521201251. The next prime is 18816521201347. The reversal of 18816521201280 is 8210212561881.

18816521201280 is a `hidden beast` number, since 1 + 8 + 8 + 16 + 521 + 20 + 12 + 80 = 666.

It is a super-2 number, since 2×18816521201280² (a number of 27 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 319 ways as a sum of consecutive naturals, for example, 40640434329 + ... + 40640434791.

It is an arithmetic number, because the mean of its divisors is an integer number (31439517120).

Almost surely, 2^{18816521201280} is an apocalyptic number.

18816521201280 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 18816521201280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40242581913600).

18816521201280 is an abundant number, since it is smaller than the sum of its proper divisors (61668642625920).

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

18816521201280 is a wasteful number, since it uses less digits than its factorization.

18816521201280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 577 (or 534 counting only the distinct ones).

The product of its (nonzero) digits is 122880, while the sum is 45.

The spelling of 18816521201280 in words is "eighteen trillion, eight hundred sixteen billion, five hundred twenty-one million, two hundred one thousand, two hundred eighty".