198540677 has 2 divisors, whose sum is σ = 198540678. Its totient is φ = 198540676.

The previous prime is 198540659. The next prime is 198540679. The reversal of 198540677 is 776045891.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 195132961 + 3407716 = 13969^2 + 1846^2 .

It is a cyclic number.

It is not a de Polignac number, because 198540677 - 2⁶ = 198540613 is a prime.

Together with 198540679, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (198540679) 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 as a sum of consecutive naturals, namely, 99270338 + 99270339.

It is an arithmetic number, because the mean of its divisors is an integer number (99270339).

Almost surely, 2^198540677 is an apocalyptic number.

It is an amenable number.

198540677 is a deficient number, since it is larger than the sum of its proper divisors (1).

198540677 is an equidigital number, since it uses as much as digits as its factorization.

198540677 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 423360, while the sum is 47.

The square root of 198540677 is about 14090.4463023710. The cubic root of 198540677 is about 583.3777119616.

The spelling of 198540677 in words is "one hundred ninety-eight million, five hundred forty thousand, six hundred seventy-seven".