145961209 has 2 divisors, whose sum is σ = 145961210. Its totient is φ = 145961208.

The previous prime is 145961203. The next prime is 145961239. The reversal of 145961209 is 902169541.

145961209 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 141134400 + 4826809 = 11880^2 + 2197^2 .

It is a cyclic number.

It is not a de Polignac number, because 145961209 - 2⁵ = 145961177 is a prime.

It is not a weakly prime, because it can be changed into another prime (145961203) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 72980604 + 72980605.

It is an arithmetic number, because the mean of its divisors is an integer number (72980605).

Almost surely, 2^145961209 is an apocalyptic number.

It is an amenable number.

145961209 is a deficient number, since it is larger than the sum of its proper divisors (1).

145961209 is an equidigital number, since it uses as much as digits as its factorization.

145961209 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 19440, while the sum is 37.

The square root of 145961209 is about 12081.4406839582. The cubic root of 145961209 is about 526.5171041335.

The spelling of 145961209 in words is "one hundred forty-five million, nine hundred sixty-one thousand, two hundred nine".