21211323212 has 12 divisors (see below), whose sum is σ = 38733720816. Its totient is φ = 10144545840.

The previous prime is 21211323193. The next prime is 21211323229. The reversal of 21211323212 is 21232311212.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 115278839 + ... + 115279022.

It is an arithmetic number, because the mean of its divisors is an integer number (3227810068).

Almost surely, 2^21211323212 is an apocalyptic number.

It is an amenable number.

21211323212 is a deficient number, since it is larger than the sum of its proper divisors (17522397604).

21211323212 is a wasteful number, since it uses less digits than its factorization.

21211323212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 230557888 (or 230557886 counting only the distinct ones).

The product of its digits is 288, while the sum is 20.

Adding to 21211323212 its reverse (21232311212), we get a palindrome (42443634424).

The spelling of 21211323212 in words is "twenty-one billion, two hundred eleven million, three hundred twenty-three thousand, two hundred twelve".