21231201 has 16 divisors (see below), whose sum is σ = 28892160. Its totient is φ = 13865040.

The previous prime is 21231173. The next prime is 21231241. The reversal of 21231201 is 10213212.

It is not a de Polignac number, because 21231201 - 2⁹ = 21230689 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21231241) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 55830 + ... + 56208.

It is an arithmetic number, because the mean of its divisors is an integer number (1805760).

Almost surely, 2^21231201 is an apocalyptic number.

It is an amenable number.

21231201 is a deficient number, since it is larger than the sum of its proper divisors (7660959).

21231201 is a wasteful number, since it uses less digits than its factorization.

21231201 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 716.

The product of its (nonzero) digits is 24, while the sum is 12.

The square root of 21231201 is about 4607.7327396454. The cubic root of 21231201 is about 276.9012102808.

Adding to 21231201 its reverse (10213212), we get a palindrome (31444413).

It can be divided in two parts, 212 and 31201, that added together give a palindrome (31413).

The spelling of 21231201 in words is "twenty-one million, two hundred thirty-one thousand, two hundred one".