169989643 has 2 divisors, whose sum is σ = 169989644. Its totient is φ = 169989642.

The previous prime is 169989641. The next prime is 169989671. The reversal of 169989643 is 346989961.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 169989643 - 2¹ = 169989641 is a prime.

Together with 169989641, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (169989641) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 84994821 + 84994822.

It is an arithmetic number, because the mean of its divisors is an integer number (84994822).

Almost surely, 2^169989643 is an apocalyptic number.

169989643 is a deficient number, since it is larger than the sum of its proper divisors (1).

169989643 is an equidigital number, since it uses as much as digits as its factorization.

169989643 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2519424, while the sum is 55.

The square root of 169989643 is about 13038.0076315363. The cubic root of 169989643 is about 553.9545755959.

The spelling of 169989643 in words is "one hundred sixty-nine million, nine hundred eighty-nine thousand, six hundred forty-three".