21120121011 has 8 divisors (see below), whose sum is σ = 30720176064. Its totient is φ = 12800073320.

The previous prime is 21120121007. The next prime is 21120121021. The reversal of 21120121011 is 11012102112.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21120121011 - 2² = 21120121007 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21120121021) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 320001801 + ... + 320001866.

It is an arithmetic number, because the mean of its divisors is an integer number (3840022008).

Almost surely, 2^21120121011 is an apocalyptic number.

21120121011 is a deficient number, since it is larger than the sum of its proper divisors (9600055053).

21120121011 is a wasteful number, since it uses less digits than its factorization.

21120121011 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 640003681.

The product of its (nonzero) digits is 8, while the sum is 12.

Adding to 21120121011 its reverse (11012102112), we get a palindrome (32132223123).

The spelling of 21120121011 in words is "twenty-one billion, one hundred twenty million, one hundred twenty-one thousand, eleven".