21121021010011 has 16 divisors (see below), whose sum is σ = 22754715177600. Its totient is φ = 19488613944960.

The previous prime is 21121021009993. The next prime is 21121021010027. The reversal of 21121021010011 is 11001012012112.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 21121021010011 - 2⁴¹ = 18921997754459 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (13).

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21121021009973 and 21121021010000.

It is not an unprimeable number, because it can be changed into a prime (21121021010311) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 502704841 + ... + 502746853.

It is an arithmetic number, because the mean of its divisors is an integer number (1422169698600).

Almost surely, 2^{21121021010011} is an apocalyptic number.

21121021010011 is a deficient number, since it is larger than the sum of its proper divisors (1633694167589).

21121021010011 is a wasteful number, since it uses less digits than its factorization.

21121021010011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 56406.

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

Adding to 21121021010011 its reverse (11001012012112), we get a palindrome (32122033022123).

The spelling of 21121021010011 in words is "twenty-one trillion, one hundred twenty-one billion, twenty-one million, ten thousand, eleven".