21442732 has 12 divisors (see below), whose sum is σ = 37587816. Its totient is φ = 10703360.

The previous prime is 21442717. The next prime is 21442741. The reversal of 21442732 is 23724412.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 21442697 and 21442706.

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, 1618 + ... + 6745.

It is an arithmetic number, because the mean of its divisors is an integer number (3132318).

Almost surely, 2^21442732 is an apocalyptic number.

It is an amenable number.

21442732 is a deficient number, since it is larger than the sum of its proper divisors (16145084).

21442732 is a wasteful number, since it uses less digits than its factorization.

21442732 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9008 (or 9006 counting only the distinct ones).

The product of its digits is 2688, while the sum is 25.

The square root of 21442732 is about 4630.6297627861. The cubic root of 21442732 is about 277.8177816638.

The spelling of 21442732 in words is "twenty-one million, four hundred forty-two thousand, seven hundred thirty-two".