1966968889 has 2 divisors, whose sum is σ = 1966968890. Its totient is φ = 1966968888.

The previous prime is 1966968859. The next prime is 1966968907. The reversal of 1966968889 is 9888696691.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1832524864 + 134444025 = 42808^2 + 11595^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1966968889 is a prime.

It is a super-2 number, since 2×1966968889² = 7737933220587788642, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1966968859) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 983484444 + 983484445.

It is an arithmetic number, because the mean of its divisors is an integer number (983484445).

Almost surely, 2^1966968889 is an apocalyptic number.

It is an amenable number.

1966968889 is a deficient number, since it is larger than the sum of its proper divisors (1).

1966968889 is an equidigital number, since it uses as much as digits as its factorization.

1966968889 is an evil number, because the sum of its binary digits is even.

The product of its digits is 80621568, while the sum is 70.

The square root of 1966968889 is about 44350.5229845151. The cubic root of 1966968889 is about 1252.9464124528.

The spelling of 1966968889 in words is "one billion, nine hundred sixty-six million, nine hundred sixty-eight thousand, eight hundred eighty-nine".