20444657688 has 256 divisors, whose sum is σ = 71326080000. Its totient is φ = 5391743616.

The previous prime is 20444657687. The next prime is 20444657693. The reversal of 20444657688 is 88675644402.

It is a happy number.

20444657688 is a `hidden beast` number, since 20 + 4 + 4 + 46 + 576 + 8 + 8 = 666.

It is a Smith number, since the sum of its digits (54) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20444657687) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 952531 + ... + 973757.

It is an arithmetic number, because the mean of its divisors is an integer number (278617500).

Almost surely, 2^20444657688 is an apocalyptic number.

20444657688 is a gapful number since it is divisible by the number (28) 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 20444657688, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35663040000).

20444657688 is an abundant number, since it is smaller than the sum of its proper divisors (50881422312).

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

20444657688 is a wasteful number, since it uses less digits than its factorization.

20444657688 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21276 (or 21252 counting only the distinct ones).

The product of its (nonzero) digits is 10321920, while the sum is 54.

The spelling of 20444657688 in words is "twenty billion, four hundred forty-four million, six hundred fifty-seven thousand, six hundred eighty-eight".