442726821 has 12 divisors (see below), whose sum is σ = 649039872. Its totient is φ = 290745576.

The previous prime is 442726813. The next prime is 442726831. The reversal of 442726821 is 128627244.

It is not a de Polignac number, because 442726821 - 2³ = 442726813 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (442726811) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 366501 + ... + 367706.

It is an arithmetic number, because the mean of its divisors is an integer number (54086656).

Almost surely, 2^442726821 is an apocalyptic number.

It is an amenable number.

442726821 is a deficient number, since it is larger than the sum of its proper divisors (206313051).

442726821 is a wasteful number, since it uses less digits than its factorization.

442726821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 734280 (or 734277 counting only the distinct ones).

The product of its digits is 43008, while the sum is 36.

The square root of 442726821 is about 21041.0746160932. The cubic root of 442726821 is about 762.1584651937.

The spelling of 442726821 in words is "four hundred forty-two million, seven hundred twenty-six thousand, eight hundred twenty-one".