20644151814 has 192 divisors, whose sum is σ = 57722595840. Its totient is φ = 5232522240.

The previous prime is 20644151809. The next prime is 20644151897. The reversal of 20644151814 is 41815144602.

20644151814 is a `hidden beast` number, since 2 + 0 + 64 + 415 + 181 + 4 = 666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 1115662 + ... + 1134014.

It is an arithmetic number, because the mean of its divisors is an integer number (300638520).

Almost surely, 2^20644151814 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20644151814, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28861297920).

20644151814 is an abundant number, since it is smaller than the sum of its proper divisors (37078444026).

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

20644151814 is a wasteful number, since it uses less digits than its factorization.

20644151814 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18427 (or 18424 counting only the distinct ones).

The product of its (nonzero) digits is 30720, while the sum is 36.

The spelling of 20644151814 in words is "twenty billion, six hundred forty-four million, one hundred fifty-one thousand, eight hundred fourteen".