21131213201 has 12 divisors (see below), whose sum is σ = 24768857520. Its totient is φ = 17974199880.

The previous prime is 21131213161. The next prime is 21131213239. The reversal of 21131213201 is 10231213112.

It is not a de Polignac number, because 21131213201 - 2⁶ = 21131213137 is a prime.

It is a super-2 number, since 2×21131213201² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 21131213201.

It is not an unprimeable number, because it can be changed into a prime (21131213101) 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 11 ways as a sum of consecutive naturals, for example, 1639571 + ... + 1652408.

It is an arithmetic number, because the mean of its divisors is an integer number (2064071460).

Almost surely, 2^21131213201 is an apocalyptic number.

It is an amenable number.

21131213201 is a deficient number, since it is larger than the sum of its proper divisors (3637644319).

21131213201 is a wasteful number, since it uses less digits than its factorization.

21131213201 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3292124 (or 3292117 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 17.

Adding to 21131213201 its reverse (10231213112), we get a palindrome (31362426313).

The spelling of 21131213201 in words is "twenty-one billion, one hundred thirty-one million, two hundred thirteen thousand, two hundred one".