1998371 has 2 divisors, whose sum is σ = 1998372. Its totient is φ = 1998370.

The previous prime is 1998349. The next prime is 1998379. The reversal of 1998371 is 1738991.

It is a strong prime.

It is an emirp because it is prime and its reverse (1738991) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1998371 is a prime.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (1998379) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 999185 + 999186.

It is an arithmetic number, because the mean of its divisors is an integer number (999186).

2^1998371 is an apocalyptic number.

1998371 is a deficient number, since it is larger than the sum of its proper divisors (1).

1998371 is an equidigital number, since it uses as much as digits as its factorization.

1998371 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 13608, while the sum is 38.

The square root of 1998371 is about 1413.6375065766. The cubic root of 1998371 is about 125.9578888416.

The spelling of 1998371 in words is "one million, nine hundred ninety-eight thousand, three hundred seventy-one".