20931123413 has 2 divisors, whose sum is σ = 20931123414. Its totient is φ = 20931123412.

The previous prime is 20931123379. The next prime is 20931123427. The reversal of 20931123413 is 31432113902.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19667818564 + 1263304849 = 140242^2 + 35543^2 .

It is a cyclic number.

It is not a de Polignac number, because 20931123413 - 2³⁰ = 19857381589 is a prime.

It is a super-2 number, since 2×20931123413² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20931123713) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10465561706 + 10465561707.

It is an arithmetic number, because the mean of its divisors is an integer number (10465561707).

Almost surely, 2^20931123413 is an apocalyptic number.

It is an amenable number.

20931123413 is a deficient number, since it is larger than the sum of its proper divisors (1).

20931123413 is an equidigital number, since it uses as much as digits as its factorization.

20931123413 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3888, while the sum is 29.

The spelling of 20931123413 in words is "twenty billion, nine hundred thirty-one million, one hundred twenty-three thousand, four hundred thirteen".