209990094943 has 4 divisors (see below), whose sum is σ = 210005981640. Its totient is φ = 209974208248.

The previous prime is 209990094917. The next prime is 209990094973. The reversal of 209990094943 is 349490099902.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-209990094943 is a prime.

It is a Smith number, since the sum of its digits (58) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (209990094913) 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 in 3 ways as a sum of consecutive naturals, for example, 7923505 + ... + 7949962.

It is an arithmetic number, because the mean of its divisors is an integer number (52501495410).

Almost surely, 2^209990094943 is an apocalyptic number.

209990094943 is a deficient number, since it is larger than the sum of its proper divisors (15886697).

209990094943 is a wasteful number, since it uses less digits than its factorization.

209990094943 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15886696.

The product of its (nonzero) digits is 5668704, while the sum is 58.

The spelling of 209990094943 in words is "two hundred nine billion, nine hundred ninety million, ninety-four thousand, nine hundred forty-three".