661198 has 8 divisors (see below), whose sum is σ = 1050192. Its totient is φ = 311136.

The previous prime is 661189. The next prime is 661201. The reversal of 661198 is 891166.

It is a happy number.

661198 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a congruent number.

It is an unprimeable number.

661198 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9690 + ... + 9757.

It is an arithmetic number, because the mean of its divisors is an integer number (131274).

2⁶⁶¹¹⁹⁸ is an apocalyptic number.

661198 is a deficient number, since it is larger than the sum of its proper divisors (388994).

661198 is a wasteful number, since it uses less digits than its factorization.

661198 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19466.

The product of its digits is 2592, while the sum is 31.

The square root of 661198 is about 813.1408242119. The cubic root of 661198 is about 87.1185243230.

The spelling of 661198 in words is "six hundred sixty-one thousand, one hundred ninety-eight".