21395442 has 8 divisors (see below), whose sum is σ = 42790896. Its totient is φ = 7131812.

The previous prime is 21395419. The next prime is 21395443. The reversal of 21395442 is 24459312.

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

21395442 is an admirable number.

It is not an unprimeable number, because it can be changed into a prime (21395443) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1782948 + ... + 1782959.

It is an arithmetic number, because the mean of its divisors is an integer number (5348862).

Almost surely, 2^21395442 is an apocalyptic number.

21395442 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

21395442 is a wasteful number, since it uses less digits than its factorization.

21395442 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3565912.

The product of its digits is 8640, while the sum is 30.

The square root of 21395442 is about 4625.5207274425. The cubic root of 21395442 is about 277.6133973691.

The spelling of 21395442 in words is "twenty-one million, three hundred ninety-five thousand, four hundred forty-two".