21936806 has 8 divisors (see below), whose sum is σ = 33526224. Its totient is φ = 10761400.

The previous prime is 21936797. The next prime is 21936821. The reversal of 21936806 is 60863912.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 103370 + ... + 103581.

It is an arithmetic number, because the mean of its divisors is an integer number (4190778).

Almost surely, 2^21936806 is an apocalyptic number.

21936806 is a deficient number, since it is larger than the sum of its proper divisors (11589418).

21936806 is a wasteful number, since it uses less digits than its factorization.

21936806 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 207006.

The product of its (nonzero) digits is 15552, while the sum is 35.

The square root of 21936806 is about 4683.6744122537. The cubic root of 21936806 is about 279.9353847498.

The spelling of 21936806 in words is "twenty-one million, nine hundred thirty-six thousand, eight hundred six".