198906861 has 4 divisors (see below), whose sum is σ = 265209152. Its totient is φ = 132604572.

The previous prime is 198906847. The next prime is 198906887. The reversal of 198906861 is 168609891.

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 198906861 - 2⁹ = 198906349 is a prime.

198906861 is a strobogrammatic number because it is the same when read upside-down.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 198906861.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (198906821) 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, 33151141 + ... + 33151146.

It is an arithmetic number, because the mean of its divisors is an integer number (66302288).

Almost surely, 2^198906861 is an apocalyptic number.

It is an amenable number.

198906861 is a deficient number, since it is larger than the sum of its proper divisors (66302291).

198906861 is an equidigital number, since it uses as much as digits as its factorization.

198906861 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 66302290.

The product of its (nonzero) digits is 186624, while the sum is 48.

The square root of 198906861 is about 14103.4343689755. The cubic root of 198906861 is about 583.7361479716.

The spelling of 198906861 in words is "one hundred ninety-eight million, nine hundred six thousand, eight hundred sixty-one".