442289921 has 8 divisors (see below), whose sum is σ = 444533544. Its totient is φ = 440052480.

The previous prime is 442289917. The next prime is 442290011. The reversal of 442289921 is 129982244.

It can be written as a sum of positive squares in 4 ways, for example, as 16321600 + 425968321 = 4040^2 + 20639^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 442289921 - 2² = 442289917 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (442489921) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 205511 + ... + 207651.

It is an arithmetic number, because the mean of its divisors is an integer number (55566693).

Almost surely, 2^442289921 is an apocalyptic number.

It is an amenable number.

442289921 is a deficient number, since it is larger than the sum of its proper divisors (2243623).

442289921 is a wasteful number, since it uses less digits than its factorization.

442289921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3091.

The product of its digits is 82944, while the sum is 41.

The square root of 442289921 is about 21030.6899791709. The cubic root of 442289921 is about 761.9076734996.

The spelling of 442289921 in words is "four hundred forty-two million, two hundred eighty-nine thousand, nine hundred twenty-one".