198621861 has 8 divisors (see below), whose sum is σ = 268559424. Its totient is φ = 130549440.

The previous prime is 198621847. The next prime is 198621869. The reversal of 198621861 is 168126891.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 198621861 - 2¹⁰ = 198620837 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (198621869) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 466036 + ... + 466461.

It is an arithmetic number, because the mean of its divisors is an integer number (33569928).

Almost surely, 2^198621861 is an apocalyptic number.

It is an amenable number.

198621861 is a deficient number, since it is larger than the sum of its proper divisors (69937563).

198621861 is an equidigital number, since it uses as much as digits as its factorization.

198621861 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 932571.

The product of its digits is 41472, while the sum is 42.

The square root of 198621861 is about 14093.3268251325. The cubic root of 198621861 is about 583.4572162106.

The spelling of 198621861 in words is "one hundred ninety-eight million, six hundred twenty-one thousand, eight hundred sixty-one".