21600660977280 has 4096 divisors, whose sum is σ = 101749063680000. Its totient is φ = 4255206359040.

The previous prime is 21600660977263. The next prime is 21600660977303. The reversal of 21600660977280 is 8277906600612.

21600660977280 is a `hidden beast` number, since 2 + 1 + 6 + 0 + 0 + 6 + 609 + 7 + 7 + 28 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a polite number, since it can be written in 511 ways as a sum of consecutive naturals, for example, 273426088281 + ... + 273426088359.

It is an arithmetic number, because the mean of its divisors is an integer number (24841080000).

Almost surely, 2^{21600660977280} is an apocalyptic number.

21600660977280 is a gapful number since it is divisible by the number (20) 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 21600660977280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (50874531840000).

21600660977280 is an abundant number, since it is smaller than the sum of its proper divisors (80148402702720).

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

21600660977280 is an equidigital number, since it uses as much as digits as its factorization.

21600660977280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 239 (or 209 counting only the distinct ones).

The product of its (nonzero) digits is 3048192, while the sum is 54.

The spelling of 21600660977280 in words is "twenty-one trillion, six hundred billion, six hundred sixty million, nine hundred seventy-seven thousand, two hundred eighty".