21305807752320 has 1536 divisors, whose sum is σ = 97917977364480. Its totient is φ = 4140762660864.

The previous prime is 21305807752253. The next prime is 21305807752373. The reversal of 21305807752320 is 2325770850312.

21305807752320 is a `hidden beast` number, since 2 + 1 + 3 + 0 + 58 + 0 + 77 + 523 + 2 + 0 = 666.

It is a super-3 number, since 3×21305807752320³ (a number of 41 digits) contains 333 as substring.

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 191 ways as a sum of consecutive naturals, for example, 418778404 + ... + 418829276.

It is an arithmetic number, because the mean of its divisors is an integer number (63748683180).

Almost surely, 2^{21305807752320} is an apocalyptic number.

21305807752320 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 21305807752320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (48958988682240).

21305807752320 is an abundant number, since it is smaller than the sum of its proper divisors (76612169612160).

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

21305807752320 is a wasteful number, since it uses less digits than its factorization.

21305807752320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 50982 (or 50967 counting only the distinct ones).

The product of its (nonzero) digits is 705600, while the sum is 45.

The spelling of 21305807752320 in words is "twenty-one trillion, three hundred five billion, eight hundred seven million, seven hundred fifty-two thousand, three hundred twenty".