21210001211011 has 4 divisors (see below), whose sum is σ = 21210906986712. Its totient is φ = 21209095435312.

The previous prime is 21210001210921. The next prime is 21210001211081. The reversal of 21210001211011 is 11011210001212.

It is a happy number.

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 21210001211011 - 2¹⁵ = 21210001178243 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21210001210982 and 21210001211000.

It is not an unprimeable number, because it can be changed into a prime (21210001211081) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 452852725 + ... + 452899558.

It is an arithmetic number, because the mean of its divisors is an integer number (5302726746678).

Almost surely, 2^{21210001211011} is an apocalyptic number.

21210001211011 is a deficient number, since it is larger than the sum of its proper divisors (905775701).

21210001211011 is an equidigital number, since it uses as much as digits as its factorization.

21210001211011 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 905775700.

The product of its (nonzero) digits is 8, while the sum is 13.

Adding to 21210001211011 its reverse (11011210001212), we get a palindrome (32221211212223).

The spelling of 21210001211011 in words is "twenty-one trillion, two hundred ten billion, one million, two hundred eleven thousand, eleven".