1986889 has 2 divisors, whose sum is σ = 1986890. Its totient is φ = 1986888.

The previous prime is 1986871. The next prime is 1986893. The reversal of 1986889 is 9886891.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1334025 + 652864 = 1155^2 + 808^2 .

It is a cyclic number.

It is not a de Polignac number, because 1986889 - 2¹¹ = 1984841 is a prime.

It is not a weakly prime, because it can be changed into another prime (1986839) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 993444 + 993445.

It is an arithmetic number, because the mean of its divisors is an integer number (993445).

2^1986889 is an apocalyptic number.

It is an amenable number.

1986889 is a deficient number, since it is larger than the sum of its proper divisors (1).

1986889 is an equidigital number, since it uses as much as digits as its factorization.

1986889 is an evil number, because the sum of its binary digits is even.

The product of its digits is 248832, while the sum is 49.

The square root of 1986889 is about 1409.5705019615. The cubic root of 1986889 is about 125.7161874343.

The spelling of 1986889 in words is "one million, nine hundred eighty-six thousand, eight hundred eighty-nine".