442523021 has 8 divisors (see below), whose sum is σ = 447572664. Its totient is φ = 437483520.

The previous prime is 442523009. The next prime is 442523027. The reversal of 442523021 is 120325244.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 1060900 + 441462121 = 1030^2 + 21011^2 .

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 442523021 - 2¹⁰ = 442521997 is a prime.

It is a super-2 number, since 2×442523021² = 391653248229932882, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (442523027) 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, 115781 + ... + 119541.

It is an arithmetic number, because the mean of its divisors is an integer number (55946583).

Almost surely, 2^442523021 is an apocalyptic number.

It is an amenable number.

442523021 is a deficient number, since it is larger than the sum of its proper divisors (5049643).

442523021 is a wasteful number, since it uses less digits than its factorization.

442523021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5071.

The product of its (nonzero) digits is 1920, while the sum is 23.

The square root of 442523021 is about 21036.2311500896. The cubic root of 442523021 is about 762.0414993599.

Adding to 442523021 its reverse (120325244), we get a palindrome (562848265).

The spelling of 442523021 in words is "four hundred forty-two million, five hundred twenty-three thousand, twenty-one".