21894342 has 8 divisors (see below), whose sum is σ = 43788696. Its totient is φ = 7298112.

The previous prime is 21894331. The next prime is 21894347. The reversal of 21894342 is 24349812.

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

21894342 is an admirable number.

It is a super-2 number, since 2×21894342² = 958724423225928, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21894347) by changing a digit.

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, 1824523 + ... + 1824534.

It is an arithmetic number, because the mean of its divisors is an integer number (5473587).

Almost surely, 2^21894342 is an apocalyptic number.

21894342 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.

21894342 is a wasteful number, since it uses less digits than its factorization.

21894342 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3649062.

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

The square root of 21894342 is about 4679.1390233674. The cubic root of 21894342 is about 279.7546405004.

The spelling of 21894342 in words is "twenty-one million, eight hundred ninety-four thousand, three hundred forty-two".