231211567 has 2 divisors, whose sum is σ = 231211568. Its totient is φ = 231211566.

The previous prime is 231211553. The next prime is 231211583. The reversal of 231211567 is 765112132.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-231211567 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (231211507) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 115605783 + 115605784.

It is an arithmetic number, because the mean of its divisors is an integer number (115605784).

Almost surely, 2^231211567 is an apocalyptic number.

231211567 is a deficient number, since it is larger than the sum of its proper divisors (1).

231211567 is an equidigital number, since it uses as much as digits as its factorization.

231211567 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2520, while the sum is 28.

The square root of 231211567 is about 15205.6426039809. The cubic root of 231211567 is about 613.7665073273.

Adding to 231211567 its reverse (765112132), we get a palindrome (996323699).

The spelling of 231211567 in words is "two hundred thirty-one million, two hundred eleven thousand, five hundred sixty-seven".