821337161 has 8 divisors (see below), whose sum is σ = 824712840. Its totient is φ = 817969408.

The previous prime is 821337103. The next prime is 821337191. The reversal of 821337161 is 161733128.

It can be written as a sum of positive squares in 4 ways, for example, as 7946761 + 813390400 = 2819^2 + 28520^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-821337161 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (821337191) 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, 282065 + ... + 284961.

It is an arithmetic number, because the mean of its divisors is an integer number (103089105).

Almost surely, 2^821337161 is an apocalyptic number.

It is an amenable number.

821337161 is a deficient number, since it is larger than the sum of its proper divisors (3375679).

821337161 is a wasteful number, since it uses less digits than its factorization.

821337161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3963.

The product of its digits is 6048, while the sum is 32.

The square root of 821337161 is about 28658.9804598838. The cubic root of 821337161 is about 936.4986541240.

The spelling of 821337161 in words is "eight hundred twenty-one million, three hundred thirty-seven thousand, one hundred sixty-one".