21582382 has 4 divisors (see below), whose sum is σ = 32373576. Its totient is φ = 10791190.

The previous prime is 21582371. The next prime is 21582439. The reversal of 21582382 is 28328512.

It is a semiprime because it is the product of two primes.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

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 as a sum of consecutive naturals, namely, 5395594 + ... + 5395597.

It is an arithmetic number, because the mean of its divisors is an integer number (8093394).

Almost surely, 2^21582382 is an apocalyptic number.

21582382 is a deficient number, since it is larger than the sum of its proper divisors (10791194).

21582382 is a wasteful number, since it uses less digits than its factorization.

21582382 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10791193.

The product of its digits is 7680, while the sum is 31.

The square root of 21582382 is about 4645.6842337809. The cubic root of 21582382 is about 278.4195913543.

The spelling of 21582382 in words is "twenty-one million, five hundred eighty-two thousand, three hundred eighty-two".