209944764213 has 4 divisors (see below), whose sum is σ = 279926352288. Its totient is φ = 139963176140.

The previous prime is 209944764209. The next prime is 209944764223. The reversal of 209944764213 is 312467449902.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 209944764213 - 2² = 209944764209 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (209944764223) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 34990794033 + ... + 34990794038.

It is an arithmetic number, because the mean of its divisors is an integer number (69981588072).

Almost surely, 2^209944764213 is an apocalyptic number.

It is an amenable number.

209944764213 is a deficient number, since it is larger than the sum of its proper divisors (69981588075).

209944764213 is an equidigital number, since it uses as much as digits as its factorization.

209944764213 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 69981588074.

The product of its (nonzero) digits is 2612736, while the sum is 51.

The spelling of 209944764213 in words is "two hundred nine billion, nine hundred forty-four million, seven hundred sixty-four thousand, two hundred thirteen".