21636193 has 8 divisors (see below), whose sum is σ = 22862720. Its totient is φ = 20418480.

The previous prime is 21636187. The next prime is 21636203. The reversal of 21636193 is 39163612.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21636193 - 2⁵ = 21636161 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21636143) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3208 + ... + 7318.

It is an arithmetic number, because the mean of its divisors is an integer number (2857840).

Almost surely, 2^21636193 is an apocalyptic number.

It is an amenable number.

21636193 is a deficient number, since it is larger than the sum of its proper divisors (1226527).

21636193 is a wasteful number, since it uses less digits than its factorization.

21636193 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4407.

The product of its digits is 5832, while the sum is 31.

The square root of 21636193 is about 4651.4721325619. The cubic root of 21636193 is about 278.6507923150.

The spelling of 21636193 in words is "twenty-one million, six hundred thirty-six thousand, one hundred ninety-three".