199991677 has 2 divisors, whose sum is σ = 199991678. Its totient is φ = 199991676.

The previous prime is 199991669. The next prime is 199991683. The reversal of 199991677 is 776199991.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 198838201 + 1153476 = 14101^2 + 1074^2 .

It is a cyclic number.

It is not a de Polignac number, because 199991677 - 2³ = 199991669 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (199991377) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99995838 + 99995839.

It is an arithmetic number, because the mean of its divisors is an integer number (99995839).

Almost surely, 2^199991677 is an apocalyptic number.

It is an amenable number.

199991677 is a deficient number, since it is larger than the sum of its proper divisors (1).

199991677 is an equidigital number, since it uses as much as digits as its factorization.

199991677 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1928934, while the sum is 58.

The square root of 199991677 is about 14141.8413581825. The cubic root of 199991677 is about 584.7954353302.

The spelling of 199991677 in words is "one hundred ninety-nine million, nine hundred ninety-one thousand, six hundred seventy-seven".