20123121313 has 2 divisors, whose sum is σ = 20123121314. Its totient is φ = 20123121312.

The previous prime is 20123121269. The next prime is 20123121329. The reversal of 20123121313 is 31312132102.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 13770553104 + 6352568209 = 117348^2 + 79703^2 .

It is a cyclic number.

It is not a de Polignac number, because 20123121313 - 2²⁵ = 20089566881 is a prime.

It is a super-2 number, since 2×20123121313² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (20123121913) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10061560656 + 10061560657.

It is an arithmetic number, because the mean of its divisors is an integer number (10061560657).

Almost surely, 2^20123121313 is an apocalyptic number.

It is an amenable number.

20123121313 is a deficient number, since it is larger than the sum of its proper divisors (1).

20123121313 is an equidigital number, since it uses as much as digits as its factorization.

20123121313 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 216, while the sum is 19.

Adding to 20123121313 its reverse (31312132102), we get a palindrome (51435253415).

The spelling of 20123121313 in words is "twenty billion, one hundred twenty-three million, one hundred twenty-one thousand, three hundred thirteen".