82731321 has 8 divisors (see below), whose sum is σ = 122564960. Its totient is φ = 55154196.

The previous prime is 82731247. The next prime is 82731331. The reversal of 82731321 is 12313728.

It is not a de Polignac number, because 82731321 - 2¹³ = 82723129 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27), and also a Moran number because the ratio is a prime number: 3064123 = 82731321 / (8 + 2 + 7 + 3 + 1 + 3 + 2 + 1).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (82731331) 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, 1532035 + ... + 1532088.

It is an arithmetic number, because the mean of its divisors is an integer number (15320620).

Almost surely, 2^82731321 is an apocalyptic number.

It is an amenable number.

82731321 is a deficient number, since it is larger than the sum of its proper divisors (39833639).

82731321 is a wasteful number, since it uses less digits than its factorization.

82731321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3064132 (or 3064126 counting only the distinct ones).

The product of its digits is 2016, while the sum is 27.

The square root of 82731321 is about 9095.6759506922. The cubic root of 82731321 is about 435.7358769096.

The spelling of 82731321 in words is "eighty-two million, seven hundred thirty-one thousand, three hundred twenty-one".