20641705632 has 480 divisors, whose sum is σ = 66073480704. Its totient is φ = 6307891200.

The previous prime is 20641705631. The next prime is 20641705639. The reversal of 20641705632 is 23650714602.

20641705632 is a `hidden beast` number, since 2 + 0 + 6 + 4 + 17 + 0 + 5 + 632 = 666.

It is a super-2 number, since 2×20641705632² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (20641705631) by changing a digit.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 157570207 + ... + 157570337.

Almost surely, 2^20641705632 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 20641705632, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33036740352).

20641705632 is an abundant number, since it is smaller than the sum of its proper divisors (45431775072).

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

20641705632 is a wasteful number, since it uses less digits than its factorization.

20641705632 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 274 (or 257 counting only the distinct ones).

The product of its (nonzero) digits is 60480, while the sum is 36.

The spelling of 20641705632 in words is "twenty billion, six hundred forty-one million, seven hundred five thousand, six hundred thirty-two".