213211091 has 4 divisors (see below), whose sum is σ = 213275232. Its totient is φ = 213146952.

The previous prime is 213211067. The next prime is 213211099. The reversal of 213211091 is 190112312.

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

It is a cyclic number.

It is not a de Polignac number, because 213211091 - 2¹⁸ = 212948947 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (213211099) 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, 26795 + ... + 33828.

It is an arithmetic number, because the mean of its divisors is an integer number (53318808).

Almost surely, 2^213211091 is an apocalyptic number.

213211091 is a deficient number, since it is larger than the sum of its proper divisors (64141).

213211091 is an equidigital number, since it uses as much as digits as its factorization.

213211091 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 64140.

The product of its (nonzero) digits is 108, while the sum is 20.

The square root of 213211091 is about 14601.7495869502. The cubic root of 213211091 is about 597.4064824490.

The spelling of 213211091 in words is "two hundred thirteen million, two hundred eleven thousand, ninety-one".