20309868973 has 2 divisors, whose sum is σ = 20309868974. Its totient is φ = 20309868972.

The previous prime is 20309868967. The next prime is 20309869007. The reversal of 20309868973 is 37986890302.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 13293628804 + 7016240169 = 115298^2 + 83763^2 .

It is a cyclic number.

It is not a de Polignac number, because 20309868973 - 2⁹ = 20309868461 is a prime.

It is a super-3 number, since 3×20309868973³ (a number of 32 digits) contains 333 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20309868473) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10154934486 + 10154934487.

It is an arithmetic number, because the mean of its divisors is an integer number (10154934487).

Almost surely, 2^20309868973 is an apocalyptic number.

It is an amenable number.

20309868973 is a deficient number, since it is larger than the sum of its proper divisors (1).

20309868973 is an equidigital number, since it uses as much as digits as its factorization.

20309868973 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3919104, while the sum is 55.

The spelling of 20309868973 in words is "twenty billion, three hundred nine million, eight hundred sixty-eight thousand, nine hundred seventy-three".