199279649 has 2 divisors, whose sum is σ = 199279650. Its totient is φ = 199279648.

The previous prime is 199279631. The next prime is 199279651. The reversal of 199279649 is 946972991.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 125440000 + 73839649 = 11200^2 + 8593^2 .

It is a cyclic number.

It is not a de Polignac number, because 199279649 - 2²⁴ = 182502433 is a prime.

Together with 199279651, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 199279594 and 199279603.

It is not a weakly prime, because it can be changed into another prime (199279679) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99639824 + 99639825.

It is an arithmetic number, because the mean of its divisors is an integer number (99639825).

Almost surely, 2^199279649 is an apocalyptic number.

It is an amenable number.

199279649 is a deficient number, since it is larger than the sum of its proper divisors (1).

199279649 is an equidigital number, since it uses as much as digits as its factorization.

199279649 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2204496, while the sum is 56.

The square root of 199279649 is about 14116.6443958896. The cubic root of 199279649 is about 584.1005966462.

The spelling of 199279649 in words is "one hundred ninety-nine million, two hundred seventy-nine thousand, six hundred forty-nine".