209660104079 has 4 divisors (see below), whose sum is σ = 209992371120. Its totient is φ = 209327837040.

The previous prime is 209660104021. The next prime is 209660104081. The reversal of 209660104079 is 970401066902.

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-209660104079 is a prime.

It is a super-2 number, since 2×209660104079² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (209660104009) 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, 166132574 + ... + 166133835.

It is an arithmetic number, because the mean of its divisors is an integer number (52498092780).

Almost surely, 2^209660104079 is an apocalyptic number.

209660104079 is a deficient number, since it is larger than the sum of its proper divisors (332267041).

209660104079 is an equidigital number, since it uses as much as digits as its factorization.

209660104079 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 332267040.

The product of its (nonzero) digits is 163296, while the sum is 44.

The spelling of 209660104079 in words is "two hundred nine billion, six hundred sixty million, one hundred four thousand, seventy-nine".