442905381 has 16 divisors (see below), whose sum is σ = 665147520. Its totient is φ = 291224160.

The previous prime is 442905377. The next prime is 442905383. The reversal of 442905381 is 183509244.

442905381 is a `hidden beast` number, since 442 + 90 + 53 + 81 = 666.

It is not a de Polignac number, because 442905381 - 2² = 442905377 is a prime.

It is a super-2 number, since 2×442905381² = 392330353037510322, which contains 22 as substring.

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (442905383) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 110385 + ... + 114326.

It is an arithmetic number, because the mean of its divisors is an integer number (41571720).

Almost surely, 2^442905381 is an apocalyptic number.

It is an amenable number.

442905381 is a deficient number, since it is larger than the sum of its proper divisors (222242139).

442905381 is a wasteful number, since it uses less digits than its factorization.

442905381 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 224793 (or 224787 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 36.

The square root of 442905381 is about 21045.3173176362. The cubic root of 442905381 is about 762.2609156719.

The spelling of 442905381 in words is "four hundred forty-two million, nine hundred five thousand, three hundred eighty-one".