20408813568 has 768 divisors, whose sum is σ = 74299680000. Its totient is φ = 5449973760.

The previous prime is 20408813533. The next prime is 20408813603. The reversal of 20408813568 is 86531880402.

20408813568 is a `hidden beast` number, since 2 + 0 + 4 + 0 + 8 + 81 + 3 + 568 = 666.

It is an interprime number because it is at equal distance from previous prime (20408813533) and next prime (20408813603).

It is a tau number, because it is divible by the number of its divisors (768).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 229312468 + ... + 229312556.

It is an arithmetic number, because the mean of its divisors is an integer number (96744375).

Almost surely, 2^20408813568 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20408813568, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37149840000).

20408813568 is an abundant number, since it is smaller than the sum of its proper divisors (53890866432).

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

20408813568 is a wasteful number, since it uses less digits than its factorization.

20408813568 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 173 (or 147 counting only the distinct ones).

The product of its (nonzero) digits is 368640, while the sum is 45.

The spelling of 20408813568 in words is "twenty billion, four hundred eight million, eight hundred thirteen thousand, five hundred sixty-eight".