21000021021211 has 2 divisors, whose sum is σ = 21000021021212. Its totient is φ = 21000021021210.

The previous prime is 21000021021193. The next prime is 21000021021223. The reversal of 21000021021211 is 11212012000012.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21000021021211 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21000021021191 and 21000021021200.

It is not a weakly prime, because it can be changed into another prime (21000021025211) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10500010510605 + 10500010510606.

It is an arithmetic number, because the mean of its divisors is an integer number (10500010510606).

Almost surely, 2^{21000021021211} is an apocalyptic number.

21000021021211 is a deficient number, since it is larger than the sum of its proper divisors (1).

21000021021211 is an equidigital number, since it uses as much as digits as its factorization.

21000021021211 is an odious number, because the sum of its binary digits is odd.

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

Adding to 21000021021211 its reverse (11212012000012), we get a palindrome (32212033021223).

It can be divided in two parts, 2100002 and 1021211, that added together give a palindrome (3121213).

The spelling of 21000021021211 in words is "twenty-one trillion, twenty-one million, twenty-one thousand, two hundred eleven".