123549689 has 2 divisors, whose sum is σ = 123549690. Its totient is φ = 123549688.

The previous prime is 123549683. The next prime is 123549691. The reversal of 123549689 is 986945321.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 116748025 + 6801664 = 10805^2 + 2608^2 .

It is a cyclic number.

It is not a de Polignac number, because 123549689 - 2¹² = 123545593 is a prime.

Together with 123549691, 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 (123549683) 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, 61774844 + 61774845.

It is an arithmetic number, because the mean of its divisors is an integer number (61774845).

Almost surely, 2^123549689 is an apocalyptic number.

It is an amenable number.

123549689 is a deficient number, since it is larger than the sum of its proper divisors (1).

123549689 is an equidigital number, since it uses as much as digits as its factorization.

123549689 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 466560, while the sum is 47.

The square root of 123549689 is about 11115.2907744242. The cubic root of 123549689 is about 498.0587246545.

The spelling of 123549689 in words is "one hundred twenty-three million, five hundred forty-nine thousand, six hundred eighty-nine".