21011012102011 has 4 divisors (see below), whose sum is σ = 21011878524024. Its totient is φ = 21010145680000.

The previous prime is 21011012101991. The next prime is 21011012102083. The reversal of 21011012102011 is 11020121011012.

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 21011012102011 - 2⁷ = 21011012101883 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21011012101982 and 21011012102000.

It is not an unprimeable number, because it can be changed into a prime (21011012142011) 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, 433174630 + ... + 433223131.

It is an arithmetic number, because the mean of its divisors is an integer number (5252969631006).

Almost surely, 2^{21011012102011} is an apocalyptic number.

21011012102011 is a deficient number, since it is larger than the sum of its proper divisors (866422013).

21011012102011 is an equidigital number, since it uses as much as digits as its factorization.

21011012102011 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 866422012.

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

Adding to 21011012102011 its reverse (11020121011012), we get a palindrome (32031133113023).

The spelling of 21011012102011 in words is "twenty-one trillion, eleven billion, twelve million, one hundred two thousand, eleven".