21548216 has 32 divisors (see below), whose sum is σ = 41731200. Its totient is φ = 10426080.

The previous prime is 21548209. The next prime is 21548221. The reversal of 21548216 is 61284512.

It is a super-2 number, since 2×21548216² = 928651225565312, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 33191 + ... + 33833.

It is an arithmetic number, because the mean of its divisors is an integer number (1304100).

Almost surely, 2^21548216 is an apocalyptic number.

It is an amenable number.

21548216 is a deficient number, since it is larger than the sum of its proper divisors (20182984).

21548216 is a wasteful number, since it uses less digits than its factorization.

21548216 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 779 (or 775 counting only the distinct ones).

The product of its digits is 3840, while the sum is 29.

The square root of 21548216 is about 4642.0056010307. The cubic root of 21548216 is about 278.2725963383.

The spelling of 21548216 in words is "twenty-one million, five hundred forty-eight thousand, two hundred sixteen".