123311989 has 2 divisors, whose sum is σ = 123311990. Its totient is φ = 123311988.

The previous prime is 123311983. The next prime is 123312001. The reversal of 123311989 is 989113321.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 68062500 + 55249489 = 8250^2 + 7433^2 .

It is a cyclic number.

It is not a de Polignac number, because 123311989 - 2¹⁷ = 123180917 is a prime.

It is a super-2 number, since 2×123311989² = 30411693262272242, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (123311983) 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, 61655994 + 61655995.

It is an arithmetic number, because the mean of its divisors is an integer number (61655995).

Almost surely, 2^123311989 is an apocalyptic number.

It is an amenable number.

123311989 is a deficient number, since it is larger than the sum of its proper divisors (1).

123311989 is an equidigital number, since it uses as much as digits as its factorization.

123311989 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 11664, while the sum is 37.

The square root of 123311989 is about 11104.5931487831. The cubic root of 123311989 is about 497.7391108361.

The spelling of 123311989 in words is "one hundred twenty-three million, three hundred eleven thousand, nine hundred eighty-nine".