123402101021 has 2 divisors, whose sum is σ = 123402101022. Its totient is φ = 123402101020.

The previous prime is 123402100973. The next prime is 123402101071. The reversal of 123402101021 is 120101204321.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 84282799225 + 39119301796 = 290315^2 + 197786^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-123402101021 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (123402101071) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 61701050510 + 61701050511.

It is an arithmetic number, because the mean of its divisors is an integer number (61701050511).

Almost surely, 2^123402101021 is an apocalyptic number.

It is an amenable number.

123402101021 is a deficient number, since it is larger than the sum of its proper divisors (1).

123402101021 is an equidigital number, since it uses as much as digits as its factorization.

123402101021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 96, while the sum is 17.

Adding to 123402101021 its reverse (120101204321), we get a palindrome (243503305342).

The spelling of 123402101021 in words is "one hundred twenty-three billion, four hundred two million, one hundred one thousand, twenty-one".