8161312 has 48 divisors (see below), whose sum is σ = 16920792. Its totient is φ = 3870720.

The previous prime is 8161273. The next prime is 8161319. The reversal of 8161312 is 2131618.

It can be written as a sum of positive squares in 4 ways, for example, as 4016016 + 4145296 = 2004^2 + 2036^2 .

It is a super-2 number, since 2×8161312² = 133214027122688, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (8161319) 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, 72168 + ... + 72280.

Almost surely, 2^8161312 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 8161312, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (8460396).

8161312 is an abundant number, since it is smaller than the sum of its proper divisors (8759480).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

8161312 is a wasteful number, since it uses less digits than its factorization.

8161312 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 221 (or 213 counting only the distinct ones).

The product of its digits is 288, while the sum is 22.

The square root of 8161312 is about 2856.8010081208. The cubic root of 8161312 is about 201.3353312766.

It can be divided in two parts, 8 and 161312, that multiplied together give a square (1290496 = 1136²).

The spelling of 8161312 in words is "eight million, one hundred sixty-one thousand, three hundred twelve".