21573874 has 16 divisors (see below), whose sum is σ = 37844928. Its totient is φ = 9030672.

The previous prime is 21573863. The next prime is 21573887. The reversal of 21573874 is 47837512.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 17317 + ... + 18520.

It is an arithmetic number, because the mean of its divisors is an integer number (2365308).

Almost surely, 2^21573874 is an apocalyptic number.

21573874 is a deficient number, since it is larger than the sum of its proper divisors (16271054).

21573874 is a wasteful number, since it uses less digits than its factorization.

21573874 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35889.

The product of its digits is 47040, while the sum is 37.

The square root of 21573874 is about 4644.7684549394. The cubic root of 21573874 is about 278.3830012439.

The spelling of 21573874 in words is "twenty-one million, five hundred seventy-three thousand, eight hundred seventy-four".