155422009 has 2 divisors, whose sum is σ = 155422010. Its totient is φ = 155422008.

The previous prime is 155421983. The next prime is 155422027. The reversal of 155422009 is 900224551.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 153834409 + 1587600 = 12403^2 + 1260^2 .

It is an emirp because it is prime and its reverse (900224551) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-155422009 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (155422039) 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, 77711004 + 77711005.

It is an arithmetic number, because the mean of its divisors is an integer number (77711005).

Almost surely, 2^155422009 is an apocalyptic number.

It is an amenable number.

155422009 is a deficient number, since it is larger than the sum of its proper divisors (1).

155422009 is an equidigital number, since it uses as much as digits as its factorization.

155422009 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3600, while the sum is 28.

The square root of 155422009 is about 12466.8363669377. The cubic root of 155422009 is about 537.6555990117.

The spelling of 155422009 in words is "one hundred fifty-five million, four hundred twenty-two thousand, nine".