20859773638 has 16 divisors (see below), whose sum is σ = 34184918736. Its totient is φ = 9467619840.

The previous prime is 20859773633. The next prime is 20859773639. The reversal of 20859773638 is 83637795802.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20859773633) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 689631 + ... + 719242.

It is an arithmetic number, because the mean of its divisors is an integer number (2136557421).

Almost surely, 2^20859773638 is an apocalyptic number.

20859773638 is a deficient number, since it is larger than the sum of its proper divisors (13325145098).

20859773638 is a wasteful number, since it uses less digits than its factorization.

20859773638 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1409559.

The product of its (nonzero) digits is 15240960, while the sum is 58.

It can be divided in two parts, 20859 and 773638, that added together give a palindrome (794497).

The spelling of 20859773638 in words is "twenty billion, eight hundred fifty-nine million, seven hundred seventy-three thousand, six hundred thirty-eight".