442451021 has 4 divisors (see below), whose sum is σ = 442826844. Its totient is φ = 442075200.

The previous prime is 442451017. The next prime is 442451033. The reversal of 442451021 is 120154244.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 391842025 + 50608996 = 19795^2 + 7114^2 .

It is a cyclic number.

It is not a de Polignac number, because 442451021 - 2² = 442451017 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (442451041) 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, 186140 + ... + 188501.

It is an arithmetic number, because the mean of its divisors is an integer number (110706711).

Almost surely, 2^442451021 is an apocalyptic number.

It is an amenable number.

442451021 is a deficient number, since it is larger than the sum of its proper divisors (375823).

442451021 is a wasteful number, since it uses less digits than its factorization.

442451021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 375822.

The product of its (nonzero) digits is 1280, while the sum is 23.

The square root of 442451021 is about 21034.5197473106. The cubic root of 442451021 is about 762.0001682040. Note that the first 3 decimals are identical.

The spelling of 442451021 in words is "four hundred forty-two million, four hundred fifty-one thousand, twenty-one".