21538382 has 8 divisors (see below), whose sum is σ = 32333952. Its totient is φ = 10760400.

The previous prime is 21538379. The next prime is 21538393. The reversal of 21538382 is 28383512.

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

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 in 3 ways as a sum of consecutive naturals, for example, 719 + ... + 6602.

It is an arithmetic number, because the mean of its divisors is an integer number (4041744).

Almost surely, 2^21538382 is an apocalyptic number.

21538382 is a deficient number, since it is larger than the sum of its proper divisors (10795570).

21538382 is a wasteful number, since it uses less digits than its factorization.

21538382 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8794.

The product of its digits is 11520, while the sum is 32.

The square root of 21538382 is about 4640.9462397231. The cubic root of 21538382 is about 278.2302579670.

The spelling of 21538382 in words is "twenty-one million, five hundred thirty-eight thousand, three hundred eighty-two".