21549055 has 8 divisors (see below), whose sum is σ = 28209744. Its totient is φ = 15672000.

The previous prime is 21549049. The next prime is 21549071. The reversal of 21549055 is 55094512.

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

It is not a de Polignac number, because 21549055 - 2¹³ = 21540863 is a prime.

It is a Duffinian number.

It is a plaindrome in base 16.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 195846 + ... + 195955.

It is an arithmetic number, because the mean of its divisors is an integer number (3526218).

Almost surely, 2^21549055 is an apocalyptic number.

21549055 is a deficient number, since it is larger than the sum of its proper divisors (6660689).

21549055 is a wasteful number, since it uses less digits than its factorization.

21549055 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 391817.

The product of its (nonzero) digits is 9000, while the sum is 31.

The square root of 21549055 is about 4642.0959705719. The cubic root of 21549055 is about 278.2762078930.

The spelling of 21549055 in words is "twenty-one million, five hundred forty-nine thousand, fifty-five".