20959731786 has 32 divisors (see below), whose sum is σ = 48041441280. Its totient is φ = 5971809456.

The previous prime is 20959731721. The next prime is 20959731799. The reversal of 20959731786 is 68713795902.

It is a Smith number, since the sum of its digits (57) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 679966 + ... + 710121.

It is an arithmetic number, because the mean of its divisors is an integer number (1501295040).

Almost surely, 2^20959731786 is an apocalyptic number.

20959731786 is an abundant number, since it is smaller than the sum of its proper divisors (27081709494).

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

20959731786 is a wasteful number, since it uses less digits than its factorization.

20959731786 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1390458.

The product of its (nonzero) digits is 5715360, while the sum is 57.

The spelling of 20959731786 in words is "twenty billion, nine hundred fifty-nine million, seven hundred thirty-one thousand, seven hundred eighty-six".