198856813 has 2 divisors, whose sum is σ = 198856814. Its totient is φ = 198856812.

The previous prime is 198856807. The next prime is 198856817. The reversal of 198856813 is 318658891.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 188183524 + 10673289 = 13718^2 + 3267^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-198856813 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (198856817) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99428406 + 99428407.

It is an arithmetic number, because the mean of its divisors is an integer number (99428407).

Almost surely, 2^198856813 is an apocalyptic number.

It is an amenable number.

198856813 is a deficient number, since it is larger than the sum of its proper divisors (1).

198856813 is an equidigital number, since it uses as much as digits as its factorization.

198856813 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 414720, while the sum is 49.

The square root of 198856813 is about 14101.6599377520. The cubic root of 198856813 is about 583.6871848921.

The spelling of 198856813 in words is "one hundred ninety-eight million, eight hundred fifty-six thousand, eight hundred thirteen".