149209909 has 2 divisors, whose sum is σ = 149209910. Its totient is φ = 149209908.

The previous prime is 149209903. The next prime is 149209919. The reversal of 149209909 is 909902941.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 128187684 + 21022225 = 11322^2 + 4585^2 .

It is a cyclic number.

It is not a de Polignac number, because 149209909 - 2⁵ = 149209877 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (149209903) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 74604954 + 74604955.

It is an arithmetic number, because the mean of its divisors is an integer number (74604955).

Almost surely, 2^149209909 is an apocalyptic number.

It is an amenable number.

149209909 is a deficient number, since it is larger than the sum of its proper divisors (1).

149209909 is an equidigital number, since it uses as much as digits as its factorization.

149209909 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 52488, while the sum is 43.

The square root of 149209909 is about 12215.1507972681. The cubic root of 149209909 is about 530.3947563364.

The spelling of 149209909 in words is "one hundred forty-nine million, two hundred nine thousand, nine hundred nine".