198842779 has 2 divisors, whose sum is σ = 198842780. Its totient is φ = 198842778.

The previous prime is 198842753. The next prime is 198842789. The reversal of 198842779 is 977248891.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 198842779 - 2⁵ = 198842747 is a prime.

It is not a weakly prime, because it can be changed into another prime (198842719) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99421389 + 99421390.

It is an arithmetic number, because the mean of its divisors is an integer number (99421390).

Almost surely, 2^198842779 is an apocalyptic number.

198842779 is a deficient number, since it is larger than the sum of its proper divisors (1).

198842779 is an equidigital number, since it uses as much as digits as its factorization.

198842779 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2032128, while the sum is 55.

The square root of 198842779 is about 14101.1623279785. The cubic root of 198842779 is about 583.6734536407.

The spelling of 198842779 in words is "one hundred ninety-eight million, eight hundred forty-two thousand, seven hundred seventy-nine".