821134423 has 4 divisors (see below), whose sum is σ = 821210400. Its totient is φ = 821058448.

The previous prime is 821134411. The next prime is 821134439. The reversal of 821134423 is 324431128.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-821134423 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 821134391 and 821134400.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (828134423) 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, 18415 + ... + 44512.

It is an arithmetic number, because the mean of its divisors is an integer number (205302600).

Almost surely, 2^821134423 is an apocalyptic number.

821134423 is a deficient number, since it is larger than the sum of its proper divisors (75977).

821134423 is a wasteful number, since it uses less digits than its factorization.

821134423 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 75976.

The product of its digits is 4608, while the sum is 28.

The square root of 821134423 is about 28655.4431653046. The cubic root of 821134423 is about 936.4215930025.

The spelling of 821134423 in words is "eight hundred twenty-one million, one hundred thirty-four thousand, four hundred twenty-three".