231021406 has 16 divisors (see below), whose sum is σ = 432040320. Its totient is φ = 90008280.

The previous prime is 231021389. The next prime is 231021409. The reversal of 231021406 is 604120132.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (231021409) 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, 749916 + ... + 750223.

It is an arithmetic number, because the mean of its divisors is an integer number (27002520).

Almost surely, 2^231021406 is an apocalyptic number.

231021406 is a deficient number, since it is larger than the sum of its proper divisors (201018914).

231021406 is a wasteful number, since it uses less digits than its factorization.

231021406 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1500159.

The product of its (nonzero) digits is 288, while the sum is 19.

The square root of 231021406 is about 15199.3883429564. The cubic root of 231021406 is about 613.5981961619.

Adding to 231021406 its reverse (604120132), we get a palindrome (835141538).

It can be divided in two parts, 2310 and 21406, that added together give a square (23716 = 154²).

The spelling of 231021406 in words is "two hundred thirty-one million, twenty-one thousand, four hundred six".