21384286 has 48 divisors (see below), whose sum is σ = 41368320. Its totient is φ = 8196720.

The previous prime is 21384263. The next prime is 21384289. The reversal of 21384286 is 68248312.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21384289) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 89355 + ... + 89593.

It is an arithmetic number, because the mean of its divisors is an integer number (861840).

Almost surely, 2^21384286 is an apocalyptic number.

21384286 is a deficient number, since it is larger than the sum of its proper divisors (19984034).

21384286 is a wasteful number, since it uses less digits than its factorization.

21384286 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 349 (or 342 counting only the distinct ones).

The product of its digits is 18432, while the sum is 34.

The square root of 21384286 is about 4624.3146519241. The cubic root of 21384286 is about 277.5651379702.

The spelling of 21384286 in words is "twenty-one million, three hundred eighty-four thousand, two hundred eighty-six".