821537479 has 16 divisors (see below), whose sum is σ = 988979200. Its totient is φ = 681450840.

The previous prime is 821537449. The next prime is 821537513. The reversal of 821537479 is 974735128.

It is not a de Polignac number, because 821537479 - 2¹⁵ = 821504711 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (821537449) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 27999 + ... + 49264.

It is an arithmetic number, because the mean of its divisors is an integer number (61811200).

Almost surely, 2^821537479 is an apocalyptic number.

821537479 is a deficient number, since it is larger than the sum of its proper divisors (167441721).

821537479 is an equidigital number, since it uses as much as digits as its factorization.

821537479 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 77315 (or 77301 counting only the distinct ones).

The product of its digits is 423360, while the sum is 46.

The square root of 821537479 is about 28662.4751024750. The cubic root of 821537479 is about 936.5747829446.

The spelling of 821537479 in words is "eight hundred twenty-one million, five hundred thirty-seven thousand, four hundred seventy-nine".