21845594 has 4 divisors (see below), whose sum is σ = 32768394. Its totient is φ = 10922796.

The previous prime is 21845563. The next prime is 21845597. The reversal of 21845594 is 49554812.

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

It can be written as a sum of positive squares in only one way, i.e., 12694969 + 9150625 = 3563^2 + 3025^2 .

It is not an unprimeable number, because it can be changed into a prime (21845597) 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, 5461397 + ... + 5461400.

Almost surely, 2^21845594 is an apocalyptic number.

21845594 is a deficient number, since it is larger than the sum of its proper divisors (10922800).

21845594 is a wasteful number, since it uses less digits than its factorization.

21845594 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10922799.

The product of its digits is 57600, while the sum is 38.

The square root of 21845594 is about 4673.9270426484. The cubic root of 21845594 is about 279.5468605926.

The spelling of 21845594 in words is "twenty-one million, eight hundred forty-five thousand, five hundred ninety-four".