198388649 has 4 divisors (see below), whose sum is σ = 198660036. Its totient is φ = 198117264.

The previous prime is 198388613. The next prime is 198388661. The reversal of 198388649 is 946883891.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 946883891 = 2083 ⋅454577.

It can be written as a sum of positive squares in 2 ways, for example, as 191628649 + 6760000 = 13843^2 + 2600^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-198388649 is a prime.

It is a super-3 number, since 3×198388649³ (a number of 26 digits) contains 333 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 198388594 and 198388603.

It is not an unprimeable number, because it can be changed into a prime (198388679) 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, 134594 + ... + 136059.

It is an arithmetic number, because the mean of its divisors is an integer number (49665009).

Almost surely, 2^198388649 is an apocalyptic number.

It is an amenable number.

198388649 is a deficient number, since it is larger than the sum of its proper divisors (271387).

198388649 is an equidigital number, since it uses as much as digits as its factorization.

198388649 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 271386.

The product of its digits is 2985984, while the sum is 56.

The square root of 198388649 is about 14085.0505501400. The cubic root of 198388649 is about 583.2287712085.

The spelling of 198388649 in words is "one hundred ninety-eight million, three hundred eighty-eight thousand, six hundred forty-nine".