21856546 has 8 divisors (see below), whose sum is σ = 33915420. Its totient is φ = 10551408.

The previous prime is 21856537. The next prime is 21856579. The reversal of 21856546 is 64565812.

It can be written as a sum of positive squares in 2 ways, for example, as 21483225 + 373321 = 4635^2 + 611^2 .

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

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, 188361 + ... + 188476.

Almost surely, 2^21856546 is an apocalyptic number.

21856546 is a deficient number, since it is larger than the sum of its proper divisors (12058874).

21856546 is a wasteful number, since it uses less digits than its factorization.

21856546 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 376868.

The product of its digits is 57600, while the sum is 37.

The square root of 21856546 is about 4675.0985016361. The cubic root of 21856546 is about 279.5935684967.

The spelling of 21856546 in words is "twenty-one million, eight hundred fifty-six thousand, five hundred forty-six".