21286982 has 8 divisors (see below), whose sum is σ = 31956456. Its totient is φ = 10634832.

The previous prime is 21286981. The next prime is 21286999. The reversal of 21286982 is 28968212.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21286981) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 623 + ... + 6554.

It is an arithmetic number, because the mean of its divisors is an integer number (3994557).

Almost surely, 2^21286982 is an apocalyptic number.

21286982 is a deficient number, since it is larger than the sum of its proper divisors (10669474).

21286982 is a wasteful number, since it uses less digits than its factorization.

21286982 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8662.

The product of its digits is 27648, while the sum is 38.

The square root of 21286982 is about 4613.7817460300. The cubic root of 21286982 is about 277.1435002187.

The spelling of 21286982 in words is "twenty-one million, two hundred eighty-six thousand, nine hundred eighty-two".