21121020011 has 8 divisors (see below), whose sum is σ = 25995101664. Its totient is φ = 16711136640.

The previous prime is 21121020001. The next prime is 21121020029. The reversal of 21121020011 is 11002012112.

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 21121020011 - 2¹⁴ = 21121003627 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21121019974 and 21121020001.

It is not an unprimeable number, because it can be changed into a prime (21121020001) 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, 116049470 + ... + 116049651.

It is an arithmetic number, because the mean of its divisors is an integer number (3249387708).

Almost surely, 2^21121020011 is an apocalyptic number.

21121020011 is a deficient number, since it is larger than the sum of its proper divisors (4874081653).

21121020011 is a wasteful number, since it uses less digits than its factorization.

21121020011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 232099141.

The product of its (nonzero) digits is 8, while the sum is 11.

Adding to 21121020011 its reverse (11002012112), we get a palindrome (32123032123).

The spelling of 21121020011 in words is "twenty-one billion, one hundred twenty-one million, twenty thousand, eleven".