21454319 has 4 divisors (see below), whose sum is σ = 21666840. Its totient is φ = 21241800.

The previous prime is 21454297. The next prime is 21454333. The reversal of 21454319 is 91345412.

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

It is a cyclic number.

It is not a de Polignac number, because 21454319 - 2²⁰ = 20405743 is a prime.

It is a super-2 number, since 2×21454319² = 920575607507522, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21454291 and 21454300.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21454379) 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 in 3 ways as a sum of consecutive naturals, for example, 106109 + ... + 106310.

It is an arithmetic number, because the mean of its divisors is an integer number (5416710).

Almost surely, 2^21454319 is an apocalyptic number.

21454319 is a deficient number, since it is larger than the sum of its proper divisors (212521).

21454319 is a wasteful number, since it uses less digits than its factorization.

21454319 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 212520.

The product of its digits is 4320, while the sum is 29.

The square root of 21454319 is about 4631.8807195350. The cubic root of 21454319 is about 277.8678140785.

The spelling of 21454319 in words is "twenty-one million, four hundred fifty-four thousand, three hundred nineteen".