21210311212 has 12 divisors (see below), whose sum is σ = 38731872816. Its totient is φ = 10144061840.

The previous prime is 21210311179. The next prime is 21210311219. The reversal of 21210311212 is 21211301212.

It is not an unprimeable number, because it can be changed into a prime (21210311219) 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 3 ways as a sum of consecutive naturals, for example, 115273339 + ... + 115273522.

It is an arithmetic number, because the mean of its divisors is an integer number (3227656068).

Almost surely, 2^21210311212 is an apocalyptic number.

It is an amenable number.

21210311212 is a deficient number, since it is larger than the sum of its proper divisors (17521561604).

21210311212 is a wasteful number, since it uses less digits than its factorization.

21210311212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 230546888 (or 230546886 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 16.

Adding to 21210311212 its reverse (21211301212), we get a palindrome (42421612424).

The spelling of 21210311212 in words is "twenty-one billion, two hundred ten million, three hundred eleven thousand, two hundred twelve".