198861407 has 4 divisors (see below), whose sum is σ = 201378720. Its totient is φ = 196344096.

The previous prime is 198861389. The next prime is 198861409. The reversal of 198861407 is 704168891.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 704168891 = 41 ⋅17174851.

It is a cyclic number.

It is not a de Polignac number, because 198861407 - 2⁶ = 198861343 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (198861409) 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 3 ways as a sum of consecutive naturals, for example, 1258538 + ... + 1258695.

It is an arithmetic number, because the mean of its divisors is an integer number (50344680).

Almost surely, 2^198861407 is an apocalyptic number.

198861407 is a deficient number, since it is larger than the sum of its proper divisors (2517313).

198861407 is an equidigital number, since it uses as much as digits as its factorization.

198861407 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2517312.

The product of its (nonzero) digits is 96768, while the sum is 44.

The square root of 198861407 is about 14101.8228254364. The cubic root of 198861407 is about 583.6916796476.

The spelling of 198861407 in words is "one hundred ninety-eight million, eight hundred sixty-one thousand, four hundred seven".