21231133212 has 24 divisors (see below), whose sum is σ = 50691389056. Its totient is φ = 6912461808.

The previous prime is 21231133201. The next prime is 21231133219. The reversal of 21231133212 is 21233113212.

It is a super-2 number, since 2×21231133212² (a number of 21 digits) contains 22 as substring.

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21231133219) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 20572288 + ... + 20573319.

Almost surely, 2^21231133212 is an apocalyptic number.

It is an amenable number.

21231133212 is an abundant number, since it is smaller than the sum of its proper divisors (29460255844).

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

21231133212 is a wasteful number, since it uses less digits than its factorization.

21231133212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41145657 (or 41145655 counting only the distinct ones).

The product of its digits is 432, while the sum is 21.

Adding to 21231133212 its reverse (21233113212), we get a palindrome (42464246424).

The spelling of 21231133212 in words is "twenty-one billion, two hundred thirty-one million, one hundred thirty-three thousand, two hundred twelve".