21212131131 has 24 divisors (see below), whose sum is σ = 31127046080. Its totient is φ = 13917661056.

The previous prime is 21212131111. The next prime is 21212131153. The reversal of 21212131131 is 13113121212.

It is not a de Polignac number, because 21212131131 - 2⁶ = 21212131067 is a prime.

It is a super-2 number, since 2×21212131131² (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 (21212131111) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 174885 + ... + 270201.

Almost surely, 2^21212131131 is an apocalyptic number.

21212131131 is a deficient number, since it is larger than the sum of its proper divisors (9914914949).

21212131131 is a wasteful number, since it uses less digits than its factorization.

21212131131 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 95715 (or 95712 counting only the distinct ones).

The product of its digits is 72, while the sum is 18.

Adding to 21212131131 its reverse (13113121212), we get a palindrome (34325252343).

The spelling of 21212131131 in words is "twenty-one billion, two hundred twelve million, one hundred thirty-one thousand, one hundred thirty-one".