155442689 has 2 divisors, whose sum is σ = 155442690. Its totient is φ = 155442688.

The previous prime is 155442673. The next prime is 155442733. The reversal of 155442689 is 986244551.

It is an a-pointer prime, because the next prime (155442733) can be obtained adding 155442689 to its sum of digits (44).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 94867600 + 60575089 = 9740^2 + 7783^2 .

It is a cyclic number.

It is not a de Polignac number, because 155442689 - 2⁴ = 155442673 is a prime.

It is not a weakly prime, because it can be changed into another prime (155442659) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 77721344 + 77721345.

It is an arithmetic number, because the mean of its divisors is an integer number (77721345).

Almost surely, 2^155442689 is an apocalyptic number.

It is an amenable number.

155442689 is a deficient number, since it is larger than the sum of its proper divisors (1).

155442689 is an equidigital number, since it uses as much as digits as its factorization.

155442689 is an evil number, because the sum of its binary digits is even.

The product of its digits is 345600, while the sum is 44.

The square root of 155442689 is about 12467.6657398248. The cubic root of 155442689 is about 537.6794442503.

The spelling of 155442689 in words is "one hundred fifty-five million, four hundred forty-two thousand, six hundred eighty-nine".