198878851 has 2 divisors, whose sum is σ = 198878852. Its totient is φ = 198878850.

The previous prime is 198878753. The next prime is 198878863. The reversal of 198878851 is 158878891.

It is a strong prime.

It is an emirp because it is prime and its reverse (158878891) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 198878851 - 2¹⁷ = 198747779 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 198878792 and 198878801.

It is not a weakly prime, because it can be changed into another prime (198878891) by changing a digit.

It is a good prime.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99439425 + 99439426.

It is an arithmetic number, because the mean of its divisors is an integer number (99439426).

Almost surely, 2^198878851 is an apocalyptic number.

198878851 is a deficient number, since it is larger than the sum of its proper divisors (1).

198878851 is an equidigital number, since it uses as much as digits as its factorization.

198878851 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1290240, while the sum is 55.

The square root of 198878851 is about 14102.4413134748. The cubic root of 198878851 is about 583.7087461733.

The spelling of 198878851 in words is "one hundred ninety-eight million, eight hundred seventy-eight thousand, eight hundred fifty-one".