199421737 has 2 divisors, whose sum is σ = 199421738. Its totient is φ = 199421736.

The previous prime is 199421731. The next prime is 199421779. The reversal of 199421737 is 737124991.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 135117376 + 64304361 = 11624^2 + 8019^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-199421737 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 199421693 and 199421702.

It is not a weakly prime, because it can be changed into another prime (199421731) 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, 99710868 + 99710869.

It is an arithmetic number, because the mean of its divisors is an integer number (99710869).

Almost surely, 2^199421737 is an apocalyptic number.

It is an amenable number.

199421737 is a deficient number, since it is larger than the sum of its proper divisors (1).

199421737 is an equidigital number, since it uses as much as digits as its factorization.

199421737 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 95256, while the sum is 43.

The square root of 199421737 is about 14121.6761398922. The cubic root of 199421737 is about 584.2393864804.

The spelling of 199421737 in words is "one hundred ninety-nine million, four hundred twenty-one thousand, seven hundred thirty-seven".