149193809 has 2 divisors, whose sum is σ = 149193810. Its totient is φ = 149193808.

The previous prime is 149193799. The next prime is 149193817. The reversal of 149193809 is 908391941.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 113529025 + 35664784 = 10655^2 + 5972^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-149193809 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 149193809.

It is not a weakly prime, because it can be changed into another prime (149193829) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 74596904 + 74596905.

It is an arithmetic number, because the mean of its divisors is an integer number (74596905).

Almost surely, 2^149193809 is an apocalyptic number.

It is an amenable number.

149193809 is a deficient number, since it is larger than the sum of its proper divisors (1).

149193809 is an equidigital number, since it uses as much as digits as its factorization.

149193809 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 69984, while the sum is 44.

The square root of 149193809 is about 12214.4917618377. The cubic root of 149193809 is about 530.3756788216.

The spelling of 149193809 in words is "one hundred forty-nine million, one hundred ninety-three thousand, eight hundred nine".