21331454 has 4 divisors (see below), whose sum is σ = 31997184. Its totient is φ = 10665726.

The previous prime is 21331451. The next prime is 21331459. The reversal of 21331454 is 45413312.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21331451) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5332862 + ... + 5332865.

It is an arithmetic number, because the mean of its divisors is an integer number (7999296).

Almost surely, 2^21331454 is an apocalyptic number.

21331454 is a deficient number, since it is larger than the sum of its proper divisors (10665730).

21331454 is a wasteful number, since it uses less digits than its factorization.

21331454 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10665729.

The product of its digits is 1440, while the sum is 23.

The square root of 21331454 is about 4618.5987052352. The cubic root of 21331454 is about 277.3363653951.

Adding to 21331454 its reverse (45413312), we get a palindrome (66744766).

The spelling of 21331454 in words is "twenty-one million, three hundred thirty-one thousand, four hundred fifty-four".