20899307520 has 1008 divisors, whose sum is σ = 91776910680. Its totient is φ = 4359979008.

The previous prime is 20899307519. The next prime is 20899307543. The reversal of 20899307520 is 2570399802.

20899307520 is a `hidden beast` number, since 2 + 0 + 8 + 99 + 30 + 7 + 520 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 9625964544 + 11273342976 = 98112^2 + 106176^2 .

It is a tau number, because it is divible by the number of its divisors (1008).

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 71 ways as a sum of consecutive naturals, for example, 234823636 + ... + 234823724.

Almost surely, 2^20899307520 is an apocalyptic number.

20899307520 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 20899307520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (45888455340).

20899307520 is an abundant number, since it is smaller than the sum of its proper divisors (70877603160).

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

20899307520 is a wasteful number, since it uses less digits than its factorization.

20899307520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 153 (or 119 counting only the distinct ones).

The product of its (nonzero) digits is 272160, while the sum is 45.

The spelling of 20899307520 in words is "twenty billion, eight hundred ninety-nine million, three hundred seven thousand, five hundred twenty".