1986398443 has 2 divisors, whose sum is σ = 1986398444. Its totient is φ = 1986398442.

The previous prime is 1986398399. The next prime is 1986398461. The reversal of 1986398443 is 3448936891.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1986398443 - 2²⁹ = 1449527531 is a prime.

It is not a weakly prime, because it can be changed into another prime (1986393443) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 993199221 + 993199222.

It is an arithmetic number, because the mean of its divisors is an integer number (993199222).

Almost surely, 2^1986398443 is an apocalyptic number.

1986398443 is a deficient number, since it is larger than the sum of its proper divisors (1).

1986398443 is an equidigital number, since it uses as much as digits as its factorization.

1986398443 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4478976, while the sum is 55.

The square root of 1986398443 is about 44569.0300881677. The cubic root of 1986398443 is about 1257.0584026481.

The spelling of 1986398443 in words is "one billion, nine hundred eighty-six million, three hundred ninety-eight thousand, four hundred forty-three".