21027970722528 has 768 divisors, whose sum is σ = 78624280627200. Its totient is φ = 5309497589760.

The previous prime is 21027970722523. The next prime is 21027970722557. The reversal of 21027970722528 is 82522707972012.

It is a happy number.

21027970722528 is a `hidden beast` number, since 2 + 1 + 0 + 2 + 7 + 97 + 0 + 7 + 22 + 528 = 666.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21027970722523) by changing a digit.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 384304900 + ... + 384359612.

It is an arithmetic number, because the mean of its divisors is an integer number (102375365400).

Almost surely, 2^{21027970722528} is an apocalyptic number.

21027970722528 is a gapful number since it is divisible by the number (28) 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 21027970722528, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (39312140313600).

21027970722528 is an abundant number, since it is smaller than the sum of its proper divisors (57596309904672).

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

21027970722528 is a wasteful number, since it uses less digits than its factorization.

21027970722528 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 54912 (or 54898 counting only the distinct ones).

The product of its (nonzero) digits is 3951360, while the sum is 54.

The spelling of 21027970722528 in words is "twenty-one trillion, twenty-seven billion, nine hundred seventy million, seven hundred twenty-two thousand, five hundred twenty-eight".