21011121112 has 32 divisors (see below), whose sum is σ = 39828297600. Its totient is φ = 10390385664.

The previous prime is 21011121073. The next prime is 21011121127. The reversal of 21011121112 is 21112111012.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 21011121092 and 21011121101.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1287033 + ... + 1303255.

It is an arithmetic number, because the mean of its divisors is an integer number (1244634300).

Almost surely, 2^21011121112 is an apocalyptic number.

It is an amenable number.

21011121112 is a deficient number, since it is larger than the sum of its proper divisors (18817176488).

21011121112 is a wasteful number, since it uses less digits than its factorization.

21011121112 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17995 (or 17991 counting only the distinct ones).

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

Adding to 21011121112 its reverse (21112111012), we get a palindrome (42123232124).

The spelling of 21011121112 in words is "twenty-one billion, eleven million, one hundred twenty-one thousand, one hundred twelve".