21442330 has 32 divisors (see below), whose sum is σ = 47505024. Its totient is φ = 6785856.

The previous prime is 21442327. The next prime is 21442331. The reversal of 21442330 is 3324412.

It is a junction number, because it is equal to n+sod(n) for n = 21442298 and 21442307.

It is not an unprimeable number, because it can be changed into a prime (21442331) 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 in 15 ways as a sum of consecutive naturals, for example, 10872 + ... + 12691.

It is an arithmetic number, because the mean of its divisors is an integer number (1484532).

Almost surely, 2^21442330 is an apocalyptic number.

21442330 is an abundant number, since it is smaller than the sum of its proper divisors (26062694).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21442330 is a wasteful number, since it uses less digits than its factorization.

21442330 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23590.

The product of its (nonzero) digits is 576, while the sum is 19.

The square root of 21442330 is about 4630.5863559597. The cubic root of 21442330 is about 277.8160455130.

Adding to 21442330 its reverse (3324412), we get a palindrome (24766742).

The spelling of 21442330 in words is "twenty-one million, four hundred forty-two thousand, three hundred thirty".