21201212222211 has 8 divisors (see below), whose sum is σ = 32306609100544. Its totient is φ = 12114978412680.

The previous prime is 21201212222153. The next prime is 21201212222219. The reversal of 21201212222211 is 11222221210212.

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

It is not a de Polignac number, because 21201212222211 - 2¹¹ = 21201212220163 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21), and also a Moran number because the ratio is a prime number: 1009581534391 = 21201212222211 / (2 + 1 + 2 + 0 + 1 + 2 + 1 + 2 + 2 + 2 + 2 + 2 + 1 + 1).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21201212222219) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 504790767175 + ... + 504790767216.

It is an arithmetic number, because the mean of its divisors is an integer number (4038326137568).

Almost surely, 2^{21201212222211} is an apocalyptic number.

21201212222211 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

21201212222211 is a deficient number, since it is larger than the sum of its proper divisors (11105396878333).

21201212222211 is a wasteful number, since it uses less digits than its factorization.

21201212222211 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1009581534401.

The product of its (nonzero) digits is 256, while the sum is 21.

Adding to 21201212222211 its reverse (11222221210212), we get a palindrome (32423433432423).

The spelling of 21201212222211 in words is "twenty-one trillion, two hundred one billion, two hundred twelve million, two hundred twenty-two thousand, two hundred eleven".