123681539 has 2 divisors, whose sum is σ = 123681540. Its totient is φ = 123681538.

The previous prime is 123681527. The next prime is 123681553. The reversal of 123681539 is 935186321.

It is a happy number.

It is a weak prime.

It is an emirp because it is prime and its reverse (935186321) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 123681539 - 2²⁰ = 122632963 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (123681139) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 61840769 + 61840770.

It is an arithmetic number, because the mean of its divisors is an integer number (61840770).

Almost surely, 2^123681539 is an apocalyptic number.

123681539 is a deficient number, since it is larger than the sum of its proper divisors (1).

123681539 is an equidigital number, since it uses as much as digits as its factorization.

123681539 is an evil number, because the sum of its binary digits is even.

The product of its digits is 38880, while the sum is 38.

The square root of 123681539 is about 11121.2202118293. The cubic root of 123681539 is about 498.2358347628.

The spelling of 123681539 in words is "one hundred twenty-three million, six hundred eighty-one thousand, five hundred thirty-nine".