842133821 has 8 divisors (see below), whose sum is σ = 846833400. Its totient is φ = 837446400.

The previous prime is 842133797. The next prime is 842133823. The reversal of 842133821 is 128331248.

It can be written as a sum of positive squares in 4 ways, for example, as 300640921 + 541492900 = 17339^2 + 23270^2 .

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 842133821 - 2⁶ = 842133757 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 (842133823) 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, 159065 + ... + 164273.

It is an arithmetic number, because the mean of its divisors is an integer number (105854175).

Almost surely, 2^842133821 is an apocalyptic number.

It is an amenable number.

842133821 is a deficient number, since it is larger than the sum of its proper divisors (4699579).

842133821 is a wasteful number, since it uses less digits than its factorization.

842133821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6079.

The product of its digits is 9216, while the sum is 32.

The square root of 842133821 is about 29019.5420535886. The cubic root of 842133821 is about 944.3370660999.

The spelling of 842133821 in words is "eight hundred forty-two million, one hundred thirty-three thousand, eight hundred twenty-one".