21231106 has 8 divisors (see below), whose sum is σ = 34296444. Its totient is φ = 9798960.

The previous prime is 21231029. The next prime is 21231107. The reversal of 21231106 is 60113212.

It can be written as a sum of positive squares in 2 ways, for example, as 16883881 + 4347225 = 4109^2 + 2085^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a self number, because there is not a number n which added to its sum of digits gives 21231106.

It is not an unprimeable number, because it can be changed into a prime (21231107) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 408265 + ... + 408316.

Almost surely, 2^21231106 is an apocalyptic number.

21231106 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

21231106 is a deficient number, since it is larger than the sum of its proper divisors (13065338).

21231106 is a wasteful number, since it uses less digits than its factorization.

21231106 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 816596.

The product of its (nonzero) digits is 72, while the sum is 16.

The square root of 21231106 is about 4607.7224308762. The cubic root of 21231106 is about 276.9007972777.

Adding to 21231106 its reverse (60113212), we get a palindrome (81344318).

The spelling of 21231106 in words is "twenty-one million, two hundred thirty-one thousand, one hundred six".