155399789 has 2 divisors, whose sum is σ = 155399790. Its totient is φ = 155399788.

The previous prime is 155399773. The next prime is 155399833. The reversal of 155399789 is 987993551.

155399789 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., 155201764 + 198025 = 12458^2 + 445^2 .

It is a cyclic number.

It is not a de Polignac number, because 155399789 - 2⁴ = 155399773 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (155399749) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 77699894 + 77699895.

It is an arithmetic number, because the mean of its divisors is an integer number (77699895).

Almost surely, 2^155399789 is an apocalyptic number.

It is an amenable number.

155399789 is a deficient number, since it is larger than the sum of its proper divisors (1).

155399789 is an equidigital number, since it uses as much as digits as its factorization.

155399789 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3061800, while the sum is 56.

The square root of 155399789 is about 12465.9451707442. The cubic root of 155399789 is about 537.6299757064.

The spelling of 155399789 in words is "one hundred fifty-five million, three hundred ninety-nine thousand, seven hundred eighty-nine".