21213031331 has 8 divisors (see below), whose sum is σ = 21946944720. Its totient is φ = 20479279968.

The previous prime is 21213031321. The next prime is 21213031337. The reversal of 21213031331 is 13313031212.

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 21213031331 - 2²⁶ = 21145922467 is a prime.

It is a super-2 number, since 2×21213031331² (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 (21213031337) 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, 265040 + ... + 335666.

It is an arithmetic number, because the mean of its divisors is an integer number (2743368090).

Almost surely, 2^21213031331 is an apocalyptic number.

21213031331 is a deficient number, since it is larger than the sum of its proper divisors (733913389).

21213031331 is a wasteful number, since it uses less digits than its factorization.

21213031331 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 81013.

The product of its (nonzero) digits is 324, while the sum is 20.

Adding to 21213031331 its reverse (13313031212), we get a palindrome (34526062543).

The spelling of 21213031331 in words is "twenty-one billion, two hundred thirteen million, thirty-one thousand, three hundred thirty-one".