21312211331 has 8 divisors (see below), whose sum is σ = 22051192800. Its totient is φ = 20573501760.

The previous prime is 21312211253. The next prime is 21312211357. The reversal of 21312211331 is 13311221312.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 21312211331 - 2¹⁴ = 21312194947 is a prime.

It is a super-2 number, since 2×21312211331² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21312211031) 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, 98450 + ... + 228728.

It is an arithmetic number, because the mean of its divisors is an integer number (2756399100).

Almost surely, 2^21312211331 is an apocalyptic number.

21312211331 is a deficient number, since it is larger than the sum of its proper divisors (738981469).

21312211331 is a wasteful number, since it uses less digits than its factorization.

21312211331 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 135949.

The product of its digits is 216, while the sum is 20.

Adding to 21312211331 its reverse (13311221312), we get a palindrome (34623432643).

The spelling of 21312211331 in words is "twenty-one billion, three hundred twelve million, two hundred eleven thousand, three hundred thirty-one".