213211231 has 4 divisors (see below), whose sum is σ = 213332200. Its totient is φ = 213090264.

The previous prime is 213211213. The next prime is 213211241. The reversal of 213211231 is 132112312.

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 213211231 - 2¹⁵ = 213178463 is a prime.

It is a super-2 number, since 2×213211231² = 90918058049070722, 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 (213211241) 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, 57801 + ... + 61378.

It is an arithmetic number, because the mean of its divisors is an integer number (53333050).

Almost surely, 2^213211231 is an apocalyptic number.

213211231 is a deficient number, since it is larger than the sum of its proper divisors (120969).

213211231 is a wasteful number, since it uses less digits than its factorization.

213211231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 120968.

The product of its digits is 72, while the sum is 16.

The square root of 213211231 is about 14601.7543808955. The cubic root of 213211231 is about 597.4066132066.

Adding to 213211231 its reverse (132112312), we get a palindrome (345323543).

It can be divided in two parts, 2 and 13211231, that multiplied together give a palindrome (26422462).

The spelling of 213211231 in words is "two hundred thirteen million, two hundred eleven thousand, two hundred thirty-one".