20958779520 has 384 divisors, whose sum is σ = 83383971840. Its totient is φ = 4751695872.

The previous prime is 20958779519. The next prime is 20958779533. The reversal of 20958779520 is 2597785902.

20958779520 is a `hidden beast` number, since 2 + 0 + 9 + 587 + 7 + 9 + 52 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (384).

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 5118594 + ... + 5122686.

It is an arithmetic number, because the mean of its divisors is an integer number (217145760).

Almost surely, 2^20958779520 is an apocalyptic number.

20958779520 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 20958779520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (41691985920).

20958779520 is an abundant number, since it is smaller than the sum of its proper divisors (62425192320).

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

20958779520 is a wasteful number, since it uses less digits than its factorization.

20958779520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4252 (or 4237 counting only the distinct ones).

The product of its (nonzero) digits is 3175200, while the sum is 54.

The spelling of 20958779520 in words is "twenty billion, nine hundred fifty-eight million, seven hundred seventy-nine thousand, five hundred twenty".