213111311 has 8 divisors (see below), whose sum is σ = 249220224. Its totient is φ = 178418520.

The previous prime is 213111271. The next prime is 213111323. The reversal of 213111311 is 113111312.

It is a happy number.

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

It is a de Polignac number, because none of the positive numbers 2^k-213111311 is a prime.

It is a super-2 number, since 2×213111311² = 90832861752277442, 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 (213111211) 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, 353705 + ... + 354306.

It is an arithmetic number, because the mean of its divisors is an integer number (31152528).

Almost surely, 2^213111311 is an apocalyptic number.

213111311 is a deficient number, since it is larger than the sum of its proper divisors (36108913).

213111311 is an equidigital number, since it uses as much as digits as its factorization.

213111311 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 708061.

The product of its digits is 18, while the sum is 14.

The square root of 213111311 is about 14598.3324732656. The cubic root of 213111311 is about 597.3132751027.

Adding to 213111311 its reverse (113111312), we get a palindrome (326222623).

Subtracting from 213111311 its reverse (113111312), we obtain a palindrome (99999999).

It can be divided in two parts, 21311 and 1311, that added together give a palindrome (22622).

The spelling of 213111311 in words is "two hundred thirteen million, one hundred eleven thousand, three hundred eleven".