20644662042 has 48 divisors (see below), whose sum is σ = 46382923080. Its totient is φ = 6628406400.

The previous prime is 20644662019. The next prime is 20644662053. The reversal of 20644662042 is 24026644602.

20644662042 is a `hidden beast` number, since 2 + 0 + 6 + 446 + 6 + 204 + 2 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 8533879641 + 12110782401 = 92379^2 + 110049^2 .

It is a junction number, because it is equal to n+sod(n) for n = 20644661988 and 20644662006.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 172792 + ... + 266732.

Almost surely, 2^20644662042 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20644662042, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23191461540).

20644662042 is an abundant number, since it is smaller than the sum of its proper divisors (25738261038).

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

20644662042 is a wasteful number, since it uses less digits than its factorization.

20644662042 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 94399 (or 94396 counting only the distinct ones).

The product of its (nonzero) digits is 110592, while the sum is 36.

The spelling of 20644662042 in words is "twenty billion, six hundred forty-four million, six hundred sixty-two thousand, forty-two".