21442398 has 8 divisors (see below), whose sum is σ = 42884808. Its totient is φ = 7147464.

The previous prime is 21442391. The next prime is 21442411. The reversal of 21442398 is 89324412.

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

21442398 is an admirable number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21442391) 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, 1786861 + ... + 1786872.

It is an arithmetic number, because the mean of its divisors is an integer number (5360601).

Almost surely, 2^21442398 is an apocalyptic number.

21442398 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.

21442398 is a wasteful number, since it uses less digits than its factorization.

21442398 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3573738.

The product of its digits is 13824, while the sum is 33.

The square root of 21442398 is about 4630.5936984365. The cubic root of 21442398 is about 277.8163391918.

The spelling of 21442398 in words is "twenty-one million, four hundred forty-two thousand, three hundred ninety-eight".