1662189989 has 2 divisors, whose sum is σ = 1662189990. Its totient is φ = 1662189988.

The previous prime is 1662189959. The next prime is 1662190003. The reversal of 1662189989 is 9899812661.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1645924900 + 16265089 = 40570^2 + 4033^2 .

It is a cyclic number.

It is not a de Polignac number, because 1662189989 - 2²⁰ = 1661141413 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1662189959) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 831094994 + 831094995.

It is an arithmetic number, because the mean of its divisors is an integer number (831094995).

Almost surely, 2^1662189989 is an apocalyptic number.

It is an amenable number.

1662189989 is a deficient number, since it is larger than the sum of its proper divisors (1).

1662189989 is an equidigital number, since it uses as much as digits as its factorization.

1662189989 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3359232, while the sum is 59.

The square root of 1662189989 is about 40769.9642997146. The cubic root of 1662189989 is about 1184.5686119889.

The spelling of 1662189989 in words is "one billion, six hundred sixty-two million, one hundred eighty-nine thousand, nine hundred eighty-nine".