21020012211 has 8 divisors (see below), whose sum is σ = 30574563264. Its totient is φ = 12739401320.

The previous prime is 21020012207. The next prime is 21020012231. The reversal of 21020012211 is 11221002012.

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

It is a cyclic number.

It is not a de Polignac number, because 21020012211 - 2² = 21020012207 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21020012231) 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, 318485001 + ... + 318485066.

It is an arithmetic number, because the mean of its divisors is an integer number (3821820408).

Almost surely, 2^21020012211 is an apocalyptic number.

21020012211 is a deficient number, since it is larger than the sum of its proper divisors (9554551053).

21020012211 is a wasteful number, since it uses less digits than its factorization.

21020012211 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 636970081.

The product of its (nonzero) digits is 16, while the sum is 12.

Adding to 21020012211 its reverse (11221002012), we get a palindrome (32241014223).

The spelling of 21020012211 in words is "twenty-one billion, twenty million, twelve thousand, two hundred eleven".