198027256989 has 4 divisors (see below), whose sum is σ = 264036342656. Its totient is φ = 132018171324.

The previous prime is 198027256969. The next prime is 198027256991. The reversal of 198027256989 is 989652720891.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 198027256989 - 2¹¹ = 198027254941 is a prime.

It is a super-2 number, since 2×198027256989² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (198027256919) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 33004542829 + ... + 33004542834.

It is an arithmetic number, because the mean of its divisors is an integer number (66009085664).

Almost surely, 2^198027256989 is an apocalyptic number.

It is an amenable number.

198027256989 is a deficient number, since it is larger than the sum of its proper divisors (66009085667).

198027256989 is an equidigital number, since it uses as much as digits as its factorization.

198027256989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 66009085666.

The product of its (nonzero) digits is 39191040, while the sum is 66.

The spelling of 198027256989 in words is "one hundred ninety-eight billion, twenty-seven million, two hundred fifty-six thousand, nine hundred eighty-nine".