21454 has 8 divisors (see below), whose sum is σ = 34128. Its totient is φ = 10080.

The previous prime is 21433. The next prime is 21467. The reversal of 21454 is 45412.

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

It is an alternating number because its digits alternate between even and odd.

It is a nialpdrome in base 15.

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, 282 + ... + 349.

It is an arithmetic number, because the mean of its divisors is an integer number (4266).

2²¹⁴⁵⁴ is an apocalyptic number.

21454 is a deficient number, since it is larger than the sum of its proper divisors (12674).

21454 is a wasteful number, since it uses less digits than its factorization.

21454 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 650.

The product of its digits is 160, while the sum is 16.

The square root of 21454 is about 146.4718402970. The cubic root of 21454 is about 27.7866436885.

Adding to 21454 its reverse (45412), we get a palindrome (66866).

The spelling of 21454 in words is "twenty-one thousand, four hundred fifty-four".