21547454 has 4 divisors (see below), whose sum is σ = 32321184. Its totient is φ = 10773726.

The previous prime is 21547451. The next prime is 21547469. The reversal of 21547454 is 45474512.

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

It is a self number, because there is not a number n which added to its sum of digits gives 21547454.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21547451) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5386862 + ... + 5386865.

It is an arithmetic number, because the mean of its divisors is an integer number (8080296).

Almost surely, 2^21547454 is an apocalyptic number.

21547454 is a deficient number, since it is larger than the sum of its proper divisors (10773730).

21547454 is a wasteful number, since it uses less digits than its factorization.

21547454 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10773729.

The product of its digits is 22400, while the sum is 32.

The square root of 21547454 is about 4641.9235237130. The cubic root of 21547454 is about 278.2693161562.

The spelling of 21547454 in words is "twenty-one million, five hundred forty-seven thousand, four hundred fifty-four".