21284316 has 24 divisors (see below), whose sum is σ = 55181840. Its totient is φ = 7094736.

The previous prime is 21284299. The next prime is 21284339. The reversal of 21284316 is 61348212.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a self number, because there is not a number n which added to its sum of digits gives 21284316.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 98431 + ... + 98646.

Almost surely, 2^21284316 is an apocalyptic number.

It is an amenable number.

21284316 is an abundant number, since it is smaller than the sum of its proper divisors (33897524).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21284316 is a wasteful number, since it uses less digits than its factorization.

21284316 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 197090 (or 197082 counting only the distinct ones).

The product of its digits is 2304, while the sum is 27.

The square root of 21284316 is about 4613.4928199792. The cubic root of 21284316 is about 277.1319298386.

The spelling of 21284316 in words is "twenty-one million, two hundred eighty-four thousand, three hundred sixteen".