123906689 has 2 divisors, whose sum is σ = 123906690. Its totient is φ = 123906688.

The previous prime is 123906683. The next prime is 123906691. The reversal of 123906689 is 986609321.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 123032464 + 874225 = 11092^2 + 935^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-123906689 is a prime.

Together with 123906691, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (123906683) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 61953344 + 61953345.

It is an arithmetic number, because the mean of its divisors is an integer number (61953345).

Almost surely, 2^123906689 is an apocalyptic number.

It is an amenable number.

123906689 is a deficient number, since it is larger than the sum of its proper divisors (1).

123906689 is an equidigital number, since it uses as much as digits as its factorization.

123906689 is an evil number, because the sum of its binary digits is even.

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

The square root of 123906689 is about 11131.3381495667. The cubic root of 123906689 is about 498.5379811686.

The spelling of 123906689 in words is "one hundred twenty-three million, nine hundred six thousand, six hundred eighty-nine".