21857264208000 has 2880 divisors, whose sum is σ = 94274793292680. Its totient is φ = 4988185804800.

The previous prime is 21857264207971. The next prime is 21857264208023. The reversal of 21857264208000 is 80246275812.

21857264208000 is a `hidden beast` number, since 2 + 1 + 85 + 72 + 6 + 420 + 80 + 0 + 0 = 666.

It can be written as a sum of positive squares in 12 ways, for example, as 276482465856 + 21580781742144 = 525816^2 + 4645512^2 .

It is a tau number, because it is divible by the number of its divisors (2880).

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

It is an unprimeable number.

It is a polite number, since it can be written in 359 ways as a sum of consecutive naturals, for example, 326227823967 + ... + 326227824033.

Almost surely, 2^{21857264208000} is an apocalyptic number.

21857264208000 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 21857264208000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (47137396646340).

21857264208000 is an abundant number, since it is smaller than the sum of its proper divisors (72417529084680).

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

21857264208000 is an equidigital number, since it uses as much as digits as its factorization.

21857264208000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 222 (or 107 counting only the distinct ones).

The product of its (nonzero) digits is 430080, while the sum is 45.

The spelling of 21857264208000 in words is "twenty-one trillion, eight hundred fifty-seven billion, two hundred sixty-four million, two hundred eight thousand".