198681651 has 24 divisors (see below), whose sum is σ = 345246720. Its totient is φ = 107556336.

The previous prime is 198681641. The next prime is 198681653. The reversal of 198681651 is 156186891.

It is not a de Polignac number, because 198681651 - 2⁵ = 198681619 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 198681597 and 198681606.

It is not an unprimeable number, because it can be changed into a prime (198681653) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 81795 + ... + 84188.

It is an arithmetic number, because the mean of its divisors is an integer number (14385280).

Almost surely, 2^198681651 is an apocalyptic number.

198681651 is a deficient number, since it is larger than the sum of its proper divisors (146565069).

198681651 is a wasteful number, since it uses less digits than its factorization.

198681651 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 166015 (or 166012 counting only the distinct ones).

The product of its digits is 103680, while the sum is 45.

The square root of 198681651 is about 14095.4478822065. The cubic root of 198681651 is about 583.5157552639.

The spelling of 198681651 in words is "one hundred ninety-eight million, six hundred eighty-one thousand, six hundred fifty-one".