21012202021211 has 4 divisors (see below), whose sum is σ = 21308148528624. Its totient is φ = 20716255513800.

The previous prime is 21012202021207. The next prime is 21012202021297. The reversal of 21012202021211 is 11212020221012.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21012202021211 - 2² = 21012202021207 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21012202021211.

It is not an unprimeable number, because it can be changed into a prime (21012202021711) 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, 147973253600 + ... + 147973253741.

It is an arithmetic number, because the mean of its divisors is an integer number (5327037132156).

Almost surely, 2^{21012202021211} is an apocalyptic number.

21012202021211 is a deficient number, since it is larger than the sum of its proper divisors (295946507413).

21012202021211 is an equidigital number, since it uses as much as digits as its factorization.

21012202021211 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 295946507412.

The product of its (nonzero) digits is 64, while the sum is 17.

Adding to 21012202021211 its reverse (11212020221012), we get a palindrome (32224222242223).

The spelling of 21012202021211 in words is "twenty-one trillion, twelve billion, two hundred two million, twenty-one thousand, two hundred eleven".