209290643423999 has 8 divisors (see below), whose sum is σ = 213515163730080. Its totient is φ = 205107744007936.

The previous prime is 209290643423989. The next prime is 209290643424013. The reversal of 209290643423999 is 999324346092902.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-209290643423999 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 (209290643423929) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10405212347 + ... + 10405232460.

It is an arithmetic number, because the mean of its divisors is an integer number (26689395466260).

Almost surely, 2^{209290643423999} is an apocalyptic number.

209290643423999 is a deficient number, since it is larger than the sum of its proper divisors (4224520306081).

209290643423999 is a wasteful number, since it uses less digits than its factorization.

209290643423999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20810445009.

The product of its (nonzero) digits is 408146688, while the sum is 71.

The spelling of 209290643423999 in words is "two hundred nine trillion, two hundred ninety billion, six hundred forty-three million, four hundred twenty-three thousand, nine hundred ninety-nine".