20811768293 has 12 divisors (see below), whose sum is σ = 21820714188. Its totient is φ = 19847667840.

The previous prime is 20811768283. The next prime is 20811768319. The reversal of 20811768293 is 39286711802.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 6458051044 + 14353717249 = 80362^2 + 119807^2 .

It is not a de Polignac number, because 20811768293 - 2¹⁶ = 20811702757 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20811768233) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 119903 + ... + 236643.

It is an arithmetic number, because the mean of its divisors is an integer number (1818392849).

Almost surely, 2^20811768293 is an apocalyptic number.

20811768293 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

It is an amenable number.

20811768293 is a deficient number, since it is larger than the sum of its proper divisors (1008945895).

20811768293 is a wasteful number, since it uses less digits than its factorization.

20811768293 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 117124 (or 117101 counting only the distinct ones).

The product of its (nonzero) digits is 290304, while the sum is 47.

The spelling of 20811768293 in words is "twenty billion, eight hundred eleven million, seven hundred sixty-eight thousand, two hundred ninety-three".