155255209 has 2 divisors, whose sum is σ = 155255210. Its totient is φ = 155255208.

The previous prime is 155255207. The next prime is 155255227. The reversal of 155255209 is 902552551.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 84695209 + 70560000 = 9203^2 + 8400^2 .

It is a cyclic number.

It is not a de Polignac number, because 155255209 - 2¹ = 155255207 is a prime.

Together with 155255207, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (155255201) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 77627604 + 77627605.

It is an arithmetic number, because the mean of its divisors is an integer number (77627605).

Almost surely, 2^155255209 is an apocalyptic number.

It is an amenable number.

155255209 is a deficient number, since it is larger than the sum of its proper divisors (1).

155255209 is an equidigital number, since it uses as much as digits as its factorization.

155255209 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 22500, while the sum is 34.

The square root of 155255209 is about 12460.1448225934. The cubic root of 155255209 is about 537.4631915663.

The spelling of 155255209 in words is "one hundred fifty-five million, two hundred fifty-five thousand, two hundred nine".