20549644625664 has 432 divisors, whose sum is σ = 77757639348480. Its totient is φ = 5056644464640.

The previous prime is 20549644625617. The next prime is 20549644625669. The reversal of 20549644625664 is 46652644694502.

20549644625664 is a `hidden beast` number, since 2 + 0 + 5 + 4 + 9 + 6 + 4 + 4 + 62 + 566 + 4 = 666.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20549644625669) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 322524 + ... + 6418980.

Almost surely, 2^{20549644625664} is an apocalyptic number.

20549644625664 is a gapful number since it is divisible by the number (24) 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 20549644625664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38878819674240).

20549644625664 is an abundant number, since it is smaller than the sum of its proper divisors (57207994722816).

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

20549644625664 is a wasteful number, since it uses less digits than its factorization.

20549644625664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6096516 (or 6096499 counting only the distinct ones).

The product of its (nonzero) digits is 298598400, while the sum is 63.

The spelling of 20549644625664 in words is "twenty trillion, five hundred forty-nine billion, six hundred forty-four million, six hundred twenty-five thousand, six hundred sixty-four".