198212661 has 6 divisors (see below), whose sum is σ = 286307190. Its totient is φ = 132141768.

The previous prime is 198212653. The next prime is 198212681. The reversal of 198212661 is 166212891.

It can be written as a sum of positive squares in only one way, i.e., 182412036 + 15800625 = 13506^2 + 3975^2 .

It is not a de Polignac number, because 198212661 - 2³ = 198212653 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (198212611) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 11011806 + ... + 11011823.

It is an arithmetic number, because the mean of its divisors is an integer number (47717865).

Almost surely, 2^198212661 is an apocalyptic number.

It is an amenable number.

198212661 is a deficient number, since it is larger than the sum of its proper divisors (88094529).

198212661 is a wasteful number, since it uses less digits than its factorization.

198212661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22023635 (or 22023632 counting only the distinct ones).

The product of its digits is 10368, while the sum is 36.

The square root of 198212661 is about 14078.8018311219. The cubic root of 198212661 is about 583.0562619596.

The spelling of 198212661 in words is "one hundred ninety-eight million, two hundred twelve thousand, six hundred sixty-one".