21121002111011 has 16 divisors (see below), whose sum is σ = 24542538209280. Its totient is φ = 17963233380480.

The previous prime is 21121002110947. The next prime is 21121002111043. The reversal of 21121002111011 is 11011120012112.

It is a cyclic number.

It is not a de Polignac number, because 21121002111011 - 2⁶ = 21121002110947 is a prime.

It is a super-2 number, since 2×21121002111011² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21121002111071) 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 15 ways as a sum of consecutive naturals, for example, 338132051 + ... + 338194508.

It is an arithmetic number, because the mean of its divisors is an integer number (1533908638080).

Almost surely, 2^{21121002111011} is an apocalyptic number.

21121002111011 is a deficient number, since it is larger than the sum of its proper divisors (3421536098269).

21121002111011 is a wasteful number, since it uses less digits than its factorization.

21121002111011 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 676326754.

The product of its (nonzero) digits is 8, while the sum is 14.

Adding to 21121002111011 its reverse (11011120012112), we get a palindrome (32132122123123).

The spelling of 21121002111011 in words is "twenty-one trillion, one hundred twenty-one billion, two million, one hundred eleven thousand, eleven".