442053821 has 4 divisors (see below), whose sum is σ = 482240544. Its totient is φ = 401867100.

The previous prime is 442053817. The next prime is 442053823. The reversal of 442053821 is 128350244.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 442053821 - 2² = 442053817 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (442053823) 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, 20093345 + ... + 20093366.

It is an arithmetic number, because the mean of its divisors is an integer number (120560136).

Almost surely, 2^442053821 is an apocalyptic number.

It is an amenable number.

442053821 is a deficient number, since it is larger than the sum of its proper divisors (40186723).

442053821 is a wasteful number, since it uses less digits than its factorization.

442053821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40186722.

The product of its (nonzero) digits is 7680, while the sum is 29.

The square root of 442053821 is about 21025.0760046189. The cubic root of 442053821 is about 761.7720773584.

The spelling of 442053821 in words is "four hundred forty-two million, fifty-three thousand, eight hundred twenty-one".