21100012110 has 32 divisors (see below), whose sum is σ = 56266699680. Its totient is φ = 5626669824.

The previous prime is 21100012103. The next prime is 21100012147. The reversal of 21100012110 is 1121000112.

It is a happy number.

It is a super-2 number, since 2×21100012110² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a junction number, because it is equal to n+sod(n) for n = 21100012092 and 21100012101.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 39073827 + ... + 39074366.

It is an arithmetic number, because the mean of its divisors is an integer number (1758334365).

Almost surely, 2^21100012110 is an apocalyptic number.

21100012110 is an abundant number, since it is smaller than the sum of its proper divisors (35166687570).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21100012110 is a wasteful number, since it uses less digits than its factorization.

21100012110 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 78148209 (or 78148203 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 9.

Adding to 21100012110 its reverse (1121000112), we get a palindrome (22221012222).

The spelling of 21100012110 in words is "twenty-one billion, one hundred million, twelve thousand, one hundred ten".