827316721 has 16 divisors (see below), whose sum is σ = 1032542208. Its totient is φ = 643986000.

The previous prime is 827316719. The next prime is 827316751. The reversal of 827316721 is 127613728.

It is not a de Polignac number, because 827316721 - 2¹ = 827316719 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (827316751) 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, 75816 + ... + 86038.

It is an arithmetic number, because the mean of its divisors is an integer number (64533888).

Almost surely, 2^827316721 is an apocalyptic number.

It is an amenable number.

827316721 is a deficient number, since it is larger than the sum of its proper divisors (205225487).

827316721 is a wasteful number, since it uses less digits than its factorization.

827316721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11292.

The product of its digits is 28224, while the sum is 37.

The square root of 827316721 is about 28763.1138960996. The cubic root of 827316721 is about 938.7658168981.

The spelling of 827316721 in words is "eight hundred twenty-seven million, three hundred sixteen thousand, seven hundred twenty-one".