21355316 has 36 divisors (see below), whose sum is σ = 41221152. Its totient is φ = 9660816.

The previous prime is 21355291. The next prime is 21355351. The reversal of 21355316 is 61355312.

It is a congruent number.

It is an unprimeable number.

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 11 ways as a sum of consecutive naturals, for example, 32891 + ... + 33533.

It is an arithmetic number, because the mean of its divisors is an integer number (1145032).

Almost surely, 2^21355316 is an apocalyptic number.

It is an amenable number.

21355316 is a deficient number, since it is larger than the sum of its proper divisors (19865836).

21355316 is a wasteful number, since it uses less digits than its factorization.

21355316 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 708 (or 687 counting only the distinct ones).

The product of its digits is 2700, while the sum is 26.

The square root of 21355316 is about 4621.1812342733. The cubic root of 21355316 is about 277.4397390995.

The spelling of 21355316 in words is "twenty-one million, three hundred fifty-five thousand, three hundred sixteen".