209791213 has 8 divisors (see below), whose sum is σ = 211320032. Its totient is φ = 208268496.

The previous prime is 209791207. The next prime is 209791243. The reversal of 209791213 is 312197902.

It is a happy number.

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-209791213 is a prime.

It is a super-2 number, since 2×209791213² = 88024706104022738, which 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 (209791243) 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, 83806 + ... + 86272.

It is an arithmetic number, because the mean of its divisors is an integer number (26415004).

Almost surely, 2^209791213 is an apocalyptic number.

It is an amenable number.

209791213 is a deficient number, since it is larger than the sum of its proper divisors (1528819).

209791213 is a wasteful number, since it uses less digits than its factorization.

209791213 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3051.

The product of its (nonzero) digits is 6804, while the sum is 34.

The square root of 209791213 is about 14484.1711188456. The cubic root of 209791213 is about 594.1951436665.

The spelling of 209791213 in words is "two hundred nine million, seven hundred ninety-one thousand, two hundred thirteen".