209961713 has 24 divisors (see below), whose sum is σ = 243334368. Its totient is φ = 180440832.

The previous prime is 209961709. The next prime is 209961721. The reversal of 209961713 is 317169902.

It is a happy number.

It is not a de Polignac number, because 209961713 - 2² = 209961709 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (209961743) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 307070 + ... + 307752.

It is an arithmetic number, because the mean of its divisors is an integer number (10138932).

Almost surely, 2^209961713 is an apocalyptic number.

It is an amenable number.

209961713 is a deficient number, since it is larger than the sum of its proper divisors (33372655).

209961713 is a wasteful number, since it uses less digits than its factorization.

209961713 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 833 (or 820 counting only the distinct ones).

The product of its (nonzero) digits is 20412, while the sum is 38.

The square root of 209961713 is about 14490.0556589683. The cubic root of 209961713 is about 594.3560700745.

The spelling of 209961713 in words is "two hundred nine million, nine hundred sixty-one thousand, seven hundred thirteen".