1998315247 has 4 divisors (see below), whose sum is σ = 2005689376. Its totient is φ = 1990941120.

The previous prime is 1998315239. The next prime is 1998315251. The reversal of 1998315247 is 7425138991.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1998315247 - 2³ = 1998315239 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1998315247.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1998315047) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3686658 + ... + 3687199.

It is an arithmetic number, because the mean of its divisors is an integer number (501422344).

Almost surely, 2^1998315247 is an apocalyptic number.

1998315247 is a deficient number, since it is larger than the sum of its proper divisors (7374129).

1998315247 is an equidigital number, since it uses as much as digits as its factorization.

1998315247 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7374128.

The product of its digits is 544320, while the sum is 49.

The square root of 1998315247 is about 44702.5194703833. The cubic root of 1998315247 is about 1259.5671745494.

The spelling of 1998315247 in words is "one billion, nine hundred ninety-eight million, three hundred fifteen thousand, two hundred forty-seven".