213011231 has 4 divisors (see below), whose sum is σ = 213040464. Its totient is φ = 212982000.

The previous prime is 213011219. The next prime is 213011233. The reversal of 213011231 is 132110312.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-213011231 is a prime.

It is a super-2 number, since 2×213011231² = 90747569064270722, 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 (213011233) 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, 6131 + ... + 21531.

It is an arithmetic number, because the mean of its divisors is an integer number (53260116).

Almost surely, 2^213011231 is an apocalyptic number.

213011231 is a deficient number, since it is larger than the sum of its proper divisors (29233).

213011231 is a wasteful number, since it uses less digits than its factorization.

213011231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29232.

The product of its (nonzero) digits is 36, while the sum is 14.

The square root of 213011231 is about 14594.9042819746. The cubic root of 213011231 is about 597.2197582883.

Adding to 213011231 its reverse (132110312), we get a palindrome (345121543).

The spelling of 213011231 in words is "two hundred thirteen million, eleven thousand, two hundred thirty-one".