198309431 has 4 divisors (see below), whose sum is σ = 198662232. Its totient is φ = 197956632.

The previous prime is 198309409. The next prime is 198309457. The reversal of 198309431 is 134903891.

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 198309431 - 2⁶ = 198309367 is a prime.

It is a super-2 number, since 2×198309431² = 78653260847087522, which 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 (198309401) 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, 175556 + ... + 176681.

It is an arithmetic number, because the mean of its divisors is an integer number (49665558).

Almost surely, 2^198309431 is an apocalyptic number.

198309431 is a deficient number, since it is larger than the sum of its proper divisors (352801).

198309431 is an equidigital number, since it uses as much as digits as its factorization.

198309431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 352800.

The product of its (nonzero) digits is 23328, while the sum is 38.

The square root of 198309431 is about 14082.2381388755. The cubic root of 198309431 is about 583.1511317401.

The spelling of 198309431 in words is "one hundred ninety-eight million, three hundred nine thousand, four hundred thirty-one".