123636590989 has 2 divisors, whose sum is σ = 123636590990. Its totient is φ = 123636590988.

The previous prime is 123636590971. The next prime is 123636591031. The reversal of 123636590989 is 989095636321.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 123137828100 + 498762889 = 350910^2 + 22333^2 .

It is a cyclic number.

It is not a de Polignac number, because 123636590989 - 2²⁷ = 123502373261 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (123636590929) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 61818295494 + 61818295495.

It is an arithmetic number, because the mean of its divisors is an integer number (61818295495).

Almost surely, 2^123636590989 is an apocalyptic number.

It is an amenable number.

123636590989 is a deficient number, since it is larger than the sum of its proper divisors (1).

123636590989 is an equidigital number, since it uses as much as digits as its factorization.

123636590989 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 18895680, while the sum is 61.

The spelling of 123636590989 in words is "one hundred twenty-three billion, six hundred thirty-six million, five hundred ninety thousand, nine hundred eighty-nine".