21893842 has 8 divisors (see below), whose sum is σ = 33031116. Its totient is φ = 10883472.

The previous prime is 21893831. The next prime is 21893887. The reversal of 21893842 is 24839812.

It can be written as a sum of positive squares in 2 ways, for example, as 21724921 + 168921 = 4661^2 + 411^2 .

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

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 3 ways as a sum of consecutive naturals, for example, 31293 + ... + 31984.

Almost surely, 2^21893842 is an apocalyptic number.

21893842 is a deficient number, since it is larger than the sum of its proper divisors (11137274).

21893842 is a wasteful number, since it uses less digits than its factorization.

21893842 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 63452.

The product of its digits is 27648, while the sum is 37.

The square root of 21893842 is about 4679.0855944297. The cubic root of 21893842 is about 279.7525109032.

The spelling of 21893842 in words is "twenty-one million, eight hundred ninety-three thousand, eight hundred forty-two".