661313198 has 32 divisors (see below), whose sum is σ = 1226340864. Its totient is φ = 260449632.

The previous prime is 661313167. The next prime is 661313203. The reversal of 661313198 is 891313166.

It is a Smith number, since the sum of its digits (38) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 33311 + ... + 49317.

It is an arithmetic number, because the mean of its divisors is an integer number (38323152).

Almost surely, 2^661313198 is an apocalyptic number.

661313198 is a deficient number, since it is larger than the sum of its proper divisors (565027666).

661313198 is a wasteful number, since it uses less digits than its factorization.

661313198 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16256.

The product of its digits is 23328, while the sum is 38.

The square root of 661313198 is about 25716.0105381842. The cubic root of 661313198 is about 871.2358347172.

The spelling of 661313198 in words is "six hundred sixty-one million, three hundred thirteen thousand, one hundred ninety-eight".