123581539 has 2 divisors, whose sum is σ = 123581540. Its totient is φ = 123581538.

The previous prime is 123581519. The next prime is 123581561. The reversal of 123581539 is 935185321.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 123581539 - 2⁷ = 123581411 is a prime.

It is equal to p_7033897 and since 123581539 and 7033897 have the same sum of digits, it is a Honaker prime.

It is a junction number, because it is equal to n+sod(n) for n = 123581498 and 123581507.

It is not a weakly prime, because it can be changed into another prime (123581509) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 61790769 + 61790770.

It is an arithmetic number, because the mean of its divisors is an integer number (61790770).

Almost surely, 2^123581539 is an apocalyptic number.

123581539 is a deficient number, since it is larger than the sum of its proper divisors (1).

123581539 is an equidigital number, since it uses as much as digits as its factorization.

123581539 is an evil number, because the sum of its binary digits is even.

The product of its digits is 32400, while the sum is 37.

The square root of 123581539 is about 11116.7233931586. The cubic root of 123581539 is about 498.1015193324.

The spelling of 123581539 in words is "one hundred twenty-three million, five hundred eighty-one thousand, five hundred thirty-nine".