155911489 has 2 divisors, whose sum is σ = 155911490. Its totient is φ = 155911488.

The previous prime is 155911447. The next prime is 155911499. The reversal of 155911489 is 984119551.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 149255089 + 6656400 = 12217^2 + 2580^2 .

It is an emirp because it is prime and its reverse (984119551) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 155911489 - 2¹⁵ = 155878721 is a prime.

It is not a weakly prime, because it can be changed into another prime (155911499) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 77955744 + 77955745.

It is an arithmetic number, because the mean of its divisors is an integer number (77955745).

Almost surely, 2^155911489 is an apocalyptic number.

It is an amenable number.

155911489 is a deficient number, since it is larger than the sum of its proper divisors (1).

155911489 is an equidigital number, since it uses as much as digits as its factorization.

155911489 is an evil number, because the sum of its binary digits is even.

The product of its digits is 64800, while the sum is 43.

The square root of 155911489 is about 12486.4522183044. The cubic root of 155911489 is about 538.2194313640.

The spelling of 155911489 in words is "one hundred fifty-five million, nine hundred eleven thousand, four hundred eighty-nine".