21653382 has 8 divisors (see below), whose sum is σ = 43306776. Its totient is φ = 7217792.

The previous prime is 21653377. The next prime is 21653431. The reversal of 21653382 is 28335612.

21653382 is nontrivially palindromic in base 5.

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

21653382 is an admirable number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1804443 + ... + 1804454.

It is an arithmetic number, because the mean of its divisors is an integer number (5413347).

Almost surely, 2^21653382 is an apocalyptic number.

21653382 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

21653382 is a wasteful number, since it uses less digits than its factorization.

21653382 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3608902.

The product of its digits is 8640, while the sum is 30.

The square root of 21653382 is about 4653.3194603423. The cubic root of 21653382 is about 278.7245646991.

Adding to 21653382 its reverse (28335612), we get a palindrome (49988994).

The spelling of 21653382 in words is "twenty-one million, six hundred fifty-three thousand, three hundred eighty-two".