21024745560 has 960 divisors, whose sum is σ = 90517331520. Its totient is φ = 4337141760.

The previous prime is 21024745537. The next prime is 21024745603. The reversal of 21024745560 is 6554742012.

It is a happy number.

21024745560 is a `hidden beast` number, since 2 + 1 + 0 + 24 + 74 + 5 + 560 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 239 ways as a sum of consecutive naturals, for example, 125896597 + ... + 125896763.

It is an arithmetic number, because the mean of its divisors is an integer number (94288887).

Almost surely, 2^21024745560 is an apocalyptic number.

21024745560 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 21024745560, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (45258665760).

21024745560 is an abundant number, since it is smaller than the sum of its proper divisors (69492585960).

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

21024745560 is a wasteful number, since it uses less digits than its factorization.

21024745560 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 278 (or 258 counting only the distinct ones).

The product of its (nonzero) digits is 67200, while the sum is 36.

The spelling of 21024745560 in words is "twenty-one billion, twenty-four million, seven hundred forty-five thousand, five hundred sixty".