21272913637920 has 288 divisors, whose sum is σ = 82969144981632. Its totient is φ = 4862100013056.

The previous prime is 21272913637919. The next prime is 21272913637931. The reversal of 21272913637920 is 2973631927212.

21272913637920 is a `hidden beast` number, since 2 + 1 + 272 + 9 + 1 + 363 + 7 + 9 + 2 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (288).

It is a hoax number, since the sum of its digits (54) coincides with the sum of the digits of its distinct prime factors.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 211256704 + ... + 211357376.

It is an arithmetic number, because the mean of its divisors is an integer number (288087308964).

Almost surely, 2^{21272913637920} is an apocalyptic number.

21272913637920 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 21272913637920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (41484572490816).

21272913637920 is an abundant number, since it is smaller than the sum of its proper divisors (61696231343712).

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

21272913637920 is a wasteful number, since it uses less digits than its factorization.

21272913637920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 121664 (or 121653 counting only the distinct ones).

The product of its (nonzero) digits is 3429216, while the sum is 54.

The spelling of 21272913637920 in words is "twenty-one trillion, two hundred seventy-two billion, nine hundred thirteen million, six hundred thirty-seven thousand, nine hundred twenty".