123020420431021 has 2 divisors, whose sum is σ = 123020420431022. Its totient is φ = 123020420431020.

The previous prime is 123020420430983. The next prime is 123020420431033. The reversal of 123020420431021 is 120134024020321.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 75195588628521 + 47824831802500 = 8671539^2 + 6915550^2 .

It is a cyclic number.

It is not a de Polignac number, because 123020420431021 - 2³¹ = 123018272947373 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (123020420431921) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 61510210215510 + 61510210215511.

It is an arithmetic number, because the mean of its divisors is an integer number (61510210215511).

Almost surely, 2^{123020420431021} is an apocalyptic number.

It is an amenable number.

123020420431021 is a deficient number, since it is larger than the sum of its proper divisors (1).

123020420431021 is an equidigital number, since it uses as much as digits as its factorization.

123020420431021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2304, while the sum is 25.

Adding to 123020420431021 its reverse (120134024020321), we get a palindrome (243154444451342).

The spelling of 123020420431021 in words is "one hundred twenty-three trillion, twenty billion, four hundred twenty million, four hundred thirty-one thousand, twenty-one".