199445307649 has 9 divisors (see below), whose sum is σ = 232011443457. Its totient is φ = 170950441284.

The previous prime is 199445307641. The next prime is 199445307661. The reversal of 199445307649 is 946703544991.

The square root of 199445307649 is 446593.

It is a perfect power (a square), and thus also a powerful number.

It is not a de Polignac number, because 199445307649 - 2³ = 199445307641 is a prime.

It is a super-3 number, since 3×199445307649³ (a number of 35 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (199445307641) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 3094252 + ... + 3158050.

It is an arithmetic number, because the mean of its divisors is an integer number (25779049273).

Almost surely, 2^199445307649 is an apocalyptic number.

199445307649 is the 446593-rd square number.

199445307649 is the 223297-th centered octagonal number.

It is an amenable number.

199445307649 is a deficient number, since it is larger than the sum of its proper divisors (32566135808).

199445307649 is an frugal number, since it uses more digits than its factorization.

199445307649 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 127612 (or 63806 counting only the distinct ones).

The product of its (nonzero) digits is 29393280, while the sum is 61.

The spelling of 199445307649 in words is "one hundred ninety-nine billion, four hundred forty-five million, three hundred seven thousand, six hundred forty-nine".