21382311 has 8 divisors (see below), whose sum is σ = 30186864. Its totient is φ = 13416320.

The previous prime is 21382307. The next prime is 21382327. The reversal of 21382311 is 11328312.

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

It is a cyclic number.

It is not a de Polignac number, because 21382311 - 2² = 21382307 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21382331) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 209580 + ... + 209681.

It is an arithmetic number, because the mean of its divisors is an integer number (3773358).

Almost surely, 2^21382311 is an apocalyptic number.

21382311 is a deficient number, since it is larger than the sum of its proper divisors (8804553).

21382311 is a wasteful number, since it uses less digits than its factorization.

21382311 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 419281.

The product of its digits is 288, while the sum is 21.

The square root of 21382311 is about 4624.1011018359. The cubic root of 21382311 is about 277.5565926296.

The spelling of 21382311 in words is "twenty-one million, three hundred eighty-two thousand, three hundred eleven".