20178393408 has 196 divisors, whose sum is σ = 61662622420. Its totient is φ = 6543783936.

The previous prime is 20178393341. The next prime is 20178393413. The reversal of 20178393408 is 80439387102.

20178393408 is a `hidden beast` number, since 201 + 7 + 8 + 39 + 3 + 408 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 19289876544 + 888516864 = 138888^2 + 29808^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 27 ways as a sum of consecutive naturals, for example, 1720428 + ... + 1732116.

Almost surely, 2^20178393408 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 20178393408, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30831311210).

20178393408 is an abundant number, since it is smaller than the sum of its proper divisors (41484229012).

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

20178393408 is an equidigital number, since it uses as much as digits as its factorization.

20178393408 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11756 (or 11731 counting only the distinct ones).

The product of its (nonzero) digits is 290304, while the sum is 45.

The spelling of 20178393408 in words is "twenty billion, one hundred seventy-eight million, three hundred ninety-three thousand, four hundred eight".