21109491112 has 16 divisors (see below), whose sum is σ = 41663469600. Its totient is φ = 9999232560.

The previous prime is 21109491097. The next prime is 21109491121. The reversal of 21109491112 is 21119490112.

It is a super-2 number, since 2×21109491112² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 69438964 + ... + 69439267.

It is an arithmetic number, because the mean of its divisors is an integer number (2603966850).

Almost surely, 2^21109491112 is an apocalyptic number.

It is an amenable number.

21109491112 is a deficient number, since it is larger than the sum of its proper divisors (20553978488).

21109491112 is a wasteful number, since it uses less digits than its factorization.

21109491112 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 138878256 (or 138878252 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 31.

The spelling of 21109491112 in words is "twenty-one billion, one hundred nine million, four hundred ninety-one thousand, one hundred twelve".