21212211201 has 4 divisors (see below), whose sum is σ = 28282948272. Its totient is φ = 14141474132.

The previous prime is 21212211149. The next prime is 21212211217. The reversal of 21212211201 is 10211221212.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21212211201 - 2⁷ = 21212211073 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21212211701) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3535368531 + ... + 3535368536.

It is an arithmetic number, because the mean of its divisors is an integer number (7070737068).

Almost surely, 2^21212211201 is an apocalyptic number.

It is an amenable number.

21212211201 is a deficient number, since it is larger than the sum of its proper divisors (7070737071).

21212211201 is an equidigital number, since it uses as much as digits as its factorization.

21212211201 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7070737070.

The product of its (nonzero) digits is 32, while the sum is 15.

Adding to 21212211201 its reverse (10211221212), we get a palindrome (31423432413).

The spelling of 21212211201 in words is "twenty-one billion, two hundred twelve million, two hundred eleven thousand, two hundred one".