21738856 has 32 divisors (see below), whose sum is σ = 42094080. Its totient is φ = 10518400.

The previous prime is 21738853. The next prime is 21738877. The reversal of 21738856 is 65883712.

It is not an unprimeable number, because it can be changed into a prime (21738853) 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 7 ways as a sum of consecutive naturals, for example, 62475 + ... + 62821.

It is an arithmetic number, because the mean of its divisors is an integer number (1315440).

Almost surely, 2^21738856 is an apocalyptic number.

It is an amenable number.

21738856 is a deficient number, since it is larger than the sum of its proper divisors (20355224).

21738856 is a wasteful number, since it uses less digits than its factorization.

21738856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 585 (or 581 counting only the distinct ones).

The product of its digits is 80640, while the sum is 40.

The square root of 21738856 is about 4662.4946112569. The cubic root of 21738856 is about 279.0908265757.

The spelling of 21738856 in words is "twenty-one million, seven hundred thirty-eight thousand, eight hundred fifty-six".