442665 has 20 divisors (see below), whose sum is σ = 794244. Its totient is φ = 235872.

The previous prime is 442633. The next prime is 442691. The reversal of 442665 is 566244.

It is a happy number.

442665 is nontrivially palindromic in base 8.

It can be written as a sum of positive squares in 2 ways, for example, as 331776 + 110889 = 576^2 + 333^2 .

It is not a de Polignac number, because 442665 - 2⁵ = 442633 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is an Ulam number.

It is a Curzon number.

It is a nialpdrome in base 9.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 142 + ... + 951.

2⁴⁴²⁶⁶⁵ is an apocalyptic number.

442665 is a gapful number since it is divisible by the number (45) formed by its first and last digit.

It is an amenable number.

442665 is a deficient number, since it is larger than the sum of its proper divisors (351579).

442665 is a wasteful number, since it uses less digits than its factorization.

442665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1110 (or 1101 counting only the distinct ones).

The product of its digits is 5760, while the sum is 27.

The square root of 442665 is about 665.3307448179. The cubic root of 442665 is about 76.2122988394.

The spelling of 442665 in words is "four hundred forty-two thousand, six hundred sixty-five".