20765309886 has 48 divisors (see below), whose sum is σ = 46514782080. Its totient is φ = 6688111680.

The previous prime is 20765309849. The next prime is 20765309899. The reversal of 20765309886 is 68890356702.

It is a happy number.

20765309886 is a `hidden beast` number, since 20 + 7 + 6 + 530 + 9 + 8 + 86 = 666.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 335880 + ... + 392868.

It is an arithmetic number, because the mean of its divisors is an integer number (969057960).

Almost surely, 2^20765309886 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20765309886, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23257391040).

20765309886 is an abundant number, since it is smaller than the sum of its proper divisors (25749472194).

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

20765309886 is a wasteful number, since it uses less digits than its factorization.

20765309886 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 57681 (or 57678 counting only the distinct ones).

The product of its (nonzero) digits is 4354560, while the sum is 54.

The spelling of 20765309886 in words is "twenty billion, seven hundred sixty-five million, three hundred nine thousand, eight hundred eighty-six".