21257953045560 has 1920 divisors, whose sum is σ = 94600741752000. Its totient is φ = 4263689041920.

The previous prime is 21257953045507. The next prime is 21257953045597. The reversal of 21257953045560 is 6554035975212.

21257953045560 is a `hidden beast` number, since 2 + 1 + 2 + 5 + 7 + 9 + 5 + 30 + 45 + 560 = 666.

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

It is a junction number, because it is equal to n+sod(n) for n = 21257953045497 and 21257953045506.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 479 ways as a sum of consecutive naturals, for example, 6127975506 + ... + 6127978974.

Almost surely, 2^{21257953045560} is an apocalyptic number.

21257953045560 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 21257953045560, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (47300370876000).

21257953045560 is an abundant number, since it is smaller than the sum of its proper divisors (73342788706440).

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

21257953045560 is a wasteful number, since it uses less digits than its factorization.

21257953045560 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3568 (or 3526 counting only the distinct ones).

The product of its (nonzero) digits is 11340000, while the sum is 54.

The spelling of 21257953045560 in words is "twenty-one trillion, two hundred fifty-seven billion, nine hundred fifty-three million, forty-five thousand, five hundred sixty".