21212001211 has 8 divisors (see below), whose sum is σ = 21610473984. Its totient is φ = 20815936680.

The previous prime is 21212001199. The next prime is 21212001227. The reversal of 21212001211 is 11210021212.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21212001211 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21212001191 and 21212001200.

It is not an unprimeable number, because it can be changed into a prime (21212001241) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 584275 + ... + 619516.

It is an arithmetic number, because the mean of its divisors is an integer number (2701309248).

Almost surely, 2^21212001211 is an apocalyptic number.

21212001211 is a deficient number, since it is larger than the sum of its proper divisors (398472773).

21212001211 is a wasteful number, since it uses less digits than its factorization.

21212001211 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1204121.

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 21212001211 its reverse (11210021212), we get a palindrome (32422022423).

The spelling of 21212001211 in words is "twenty-one billion, two hundred twelve million, one thousand, two hundred eleven".