123660989 has 2 divisors, whose sum is σ = 123660990. Its totient is φ = 123660988.

The previous prime is 123660983. The next prime is 123661033. The reversal of 123660989 is 989066321.

It is an a-pointer prime, because the next prime (123661033) can be obtained adding 123660989 to its sum of digits (44).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 122832889 + 828100 = 11083^2 + 910^2 .

It is a cyclic number.

It is not a de Polignac number, because 123660989 - 2⁴ = 123660973 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (123660983) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 61830494 + 61830495.

It is an arithmetic number, because the mean of its divisors is an integer number (61830495).

Almost surely, 2^123660989 is an apocalyptic number.

It is an amenable number.

123660989 is a deficient number, since it is larger than the sum of its proper divisors (1).

123660989 is an equidigital number, since it uses as much as digits as its factorization.

123660989 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 139968, while the sum is 44.

The square root of 123660989 is about 11120.2962640390. The cubic root of 123660989 is about 498.2082388537.

The spelling of 123660989 in words is "one hundred twenty-three million, six hundred sixty thousand, nine hundred eighty-nine".