21354423 has 8 divisors (see below), whose sum is σ = 29971200. Its totient is φ = 13486968.

The previous prime is 21354413. The next prime is 21354433. The reversal of 21354423 is 32445312.

It is an interprime number because it is at equal distance from previous prime (21354413) and next prime (21354433).

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

It is not a de Polignac number, because 21354423 - 2⁴ = 21354407 is a prime.

It is a super-2 number, since 2×21354423² = 912022763325858, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21354393 and 21354402.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21354413) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 187263 + ... + 187376.

It is an arithmetic number, because the mean of its divisors is an integer number (3746400).

Almost surely, 2^21354423 is an apocalyptic number.

21354423 is a deficient number, since it is larger than the sum of its proper divisors (8616777).

21354423 is a wasteful number, since it uses less digits than its factorization.

21354423 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 374661.

The product of its digits is 2880, while the sum is 24.

The square root of 21354423 is about 4621.0846129453. The cubic root of 21354423 is about 277.4358718791.

Adding to 21354423 its reverse (32445312), we get a palindrome (53799735).

The spelling of 21354423 in words is "twenty-one million, three hundred fifty-four thousand, four hundred twenty-three".