1669193989 has 2 divisors, whose sum is σ = 1669193990. Its totient is φ = 1669193988.

The previous prime is 1669193971. The next prime is 1669194083. The reversal of 1669193989 is 9893919661.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 898021089 + 771172900 = 29967^2 + 27770^2 .

It is a cyclic number.

It is not a de Polignac number, because 1669193989 - 2²³ = 1660805381 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1669193389) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 834596994 + 834596995.

It is an arithmetic number, because the mean of its divisors is an integer number (834596995).

Almost surely, 2^1669193989 is an apocalyptic number.

It is an amenable number.

1669193989 is a deficient number, since it is larger than the sum of its proper divisors (1).

1669193989 is an equidigital number, since it uses as much as digits as its factorization.

1669193989 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5668704, while the sum is 61.

The square root of 1669193989 is about 40855.7705716096. The cubic root of 1669193989 is about 1186.2300932220.

The spelling of 1669193989 in words is "one billion, six hundred sixty-nine million, one hundred ninety-three thousand, nine hundred eighty-nine".