21610012 has 12 divisors (see below), whose sum is σ = 37850176. Its totient is φ = 10795680.

The previous prime is 21610003. The next prime is 21610019. The reversal of 21610012 is 21001612.

It is a junction number, because it is equal to n+sod(n) for n = 21609974 and 21610001.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21610019) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7312 + ... + 9832.

Almost surely, 2^21610012 is an apocalyptic number.

It is an amenable number.

21610012 is a deficient number, since it is larger than the sum of its proper divisors (16240164).

21610012 is a wasteful number, since it uses less digits than its factorization.

21610012 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4668 (or 4666 counting only the distinct ones).

The product of its (nonzero) digits is 24, while the sum is 13.

The square root of 21610012 is about 4648.6570103633. The cubic root of 21610012 is about 278.5383526178.

Adding to 21610012 its reverse (21001612), we get a palindrome (42611624).

Subtracting from 21610012 its reverse (21001612), we obtain a square (608400 = 780²).

The spelling of 21610012 in words is "twenty-one million, six hundred ten thousand, twelve".