21000112 has 40 divisors (see below), whose sum is σ = 47003936. Its totient is φ = 8902656.

The previous prime is 21000103. The next prime is 21000121. The reversal of 21000112 is 21100012.

It is an interprime number because it is at equal distance from previous prime (21000103) and next prime (21000121).

It is a Harshad number since it is a multiple of its sum of digits (7).

It is a junction number, because it is equal to n+sod(n) for n = 21000095 and 21000104.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9898 + ... + 11830.

Almost surely, 2^21000112 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21000112, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23501968).

21000112 is an abundant number, since it is smaller than the sum of its proper divisors (26003824).

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

21000112 is a wasteful number, since it uses less digits than its factorization.

21000112 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2045 (or 2039 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 7.

The square root of 21000112 is about 4582.5879151414. The cubic root of 21000112 is about 275.8929081126.

Adding to 21000112 its reverse (21100012), we get a palindrome (42100124).

It can be divided in two parts, 21000 and 112, that added together give a palindrome (21112).

The spelling of 21000112 in words is "twenty-one million, one hundred twelve", and thus it is an aban number.