21193606 has 16 divisors (see below), whose sum is σ = 37585440. Its totient is φ = 8769600.

The previous prime is 21193591. The next prime is 21193609. The reversal of 21193606 is 60639112.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21193609) by changing a digit.

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, 25695 + ... + 26506.

It is an arithmetic number, because the mean of its divisors is an integer number (2349090).

Almost surely, 2^21193606 is an apocalyptic number.

21193606 is a deficient number, since it is larger than the sum of its proper divisors (16391834).

21193606 is a wasteful number, since it uses less digits than its factorization.

21193606 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 52239.

The product of its (nonzero) digits is 1944, while the sum is 28.

The square root of 21193606 is about 4603.6513768964. The cubic root of 21193606 is about 276.7376734246.

The spelling of 21193606 in words is "twenty-one million, one hundred ninety-three thousand, six hundred six".