231213564 has 18 divisors (see below), whose sum is σ = 584456600. Its totient is φ = 77071176.

The previous prime is 231213551. The next prime is 231213571. The reversal of 231213564 is 465312132.

231213564 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (18).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 3211264 + ... + 3211335.

Almost surely, 2^231213564 is an apocalyptic number.

It is an amenable number.

231213564 is an abundant number, since it is smaller than the sum of its proper divisors (353243036).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

231213564 is a wasteful number, since it uses less digits than its factorization.

231213564 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6422609 (or 6422604 counting only the distinct ones).

The product of its digits is 4320, while the sum is 27.

The square root of 231213564 is about 15205.7082702517. The cubic root of 231213564 is about 613.7682743787.

Adding to 231213564 its reverse (465312132), we get a palindrome (696525696).

It can be divided in two parts, 2312 and 13564, that added together give a square (15876 = 126²).

The spelling of 231213564 in words is "two hundred thirty-one million, two hundred thirteen thousand, five hundred sixty-four".