123749009 has 2 divisors, whose sum is σ = 123749010. Its totient is φ = 123749008.

The previous prime is 123748987. The next prime is 123749023. The reversal of 123749009 is 900947321.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 79566400 + 44182609 = 8920^2 + 6647^2 .

It is a cyclic number.

It is not a de Polignac number, because 123749009 - 2⁸ = 123748753 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 123749009.

It is not a weakly prime, because it can be changed into another prime (123742009) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 61874504 + 61874505.

It is an arithmetic number, because the mean of its divisors is an integer number (61874505).

Almost surely, 2^123749009 is an apocalyptic number.

It is an amenable number.

123749009 is a deficient number, since it is larger than the sum of its proper divisors (1).

123749009 is an equidigital number, since it uses as much as digits as its factorization.

123749009 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 13608, while the sum is 35.

The square root of 123749009 is about 11124.2531884167. The cubic root of 123749009 is about 498.3264164865.

The spelling of 123749009 in words is "one hundred twenty-three million, seven hundred forty-nine thousand, nine".