149909 has 2 divisors, whose sum is σ = 149910. Its totient is φ = 149908.

The previous prime is 149899. The next prime is 149911. The reversal of 149909 is 909941.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 103684 + 46225 = 322^2 + 215^2 .

It is a cyclic number.

It is not a de Polignac number, because 149909 - 2⁴ = 149893 is a prime.

Together with 149911, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (149939) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 74954 + 74955.

It is an arithmetic number, because the mean of its divisors is an integer number (74955).

2¹⁴⁹⁹⁰⁹ is an apocalyptic number.

It is an amenable number.

149909 is a deficient number, since it is larger than the sum of its proper divisors (1).

149909 is an equidigital number, since it uses as much as digits as its factorization.

149909 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2916, while the sum is 32.

The square root of 149909 is about 387.1808363026. The cubic root of 149909 is about 53.1221816267.

Adding to 149909 its sum of digits (32), we get a palindrome (149941).

The spelling of 149909 in words is "one hundred forty-nine thousand, nine hundred nine".