21003112 has 16 divisors (see below), whose sum is σ = 42410340. Its totient is φ = 9693696.

The previous prime is 21003107. The next prime is 21003121. The reversal of 21003112 is 21130012.

It can be written as a sum of positive squares in 2 ways, for example, as 20738916 + 264196 = 4554^2 + 514^2 .

It is a super-2 number, since 2×21003112² = 882261427369088, which contains 22 as substring.

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 3 ways as a sum of consecutive naturals, for example, 100873 + ... + 101080.

Almost surely, 2^21003112 is an apocalyptic number.

It is an amenable number.

21003112 is an abundant number, since it is smaller than the sum of its proper divisors (21407228).

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

21003112 is a wasteful number, since it uses less digits than its factorization.

21003112 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 201972 (or 201968 counting only the distinct ones).

The product of its (nonzero) digits is 12, while the sum is 10.

The square root of 21003112 is about 4582.9152294146. The cubic root of 21003112 is about 275.9060451746.

Adding to 21003112 its reverse (21130012), we get a palindrome (42133124).

It can be divided in two parts, 21003 and 112, that added together give a triangular number (21115 = T₂₀₅).

The spelling of 21003112 in words is "twenty-one million, three thousand, one hundred twelve".