7881312 has 48 divisors (see below), whose sum is σ = 21092400. Its totient is φ = 2575872.

The previous prime is 7881287. The next prime is 7881317. The reversal of 7881312 is 2131887.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (48).

It is a self number, because there is not a number n which added to its sum of digits gives 7881312.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7881317) 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, 4314 + ... + 5862.

It is an arithmetic number, because the mean of its divisors is an integer number (439425).

Almost surely, 2^7881312 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 7881312, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (10546200).

7881312 is an abundant number, since it is smaller than the sum of its proper divisors (13211088).

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

7881312 is a wasteful number, since it uses less digits than its factorization.

7881312 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1615 (or 1607 counting only the distinct ones).

The product of its digits is 2688, while the sum is 30.

The square root of 7881312 is about 2807.3674501212. The cubic root of 7881312 is about 199.0060013510.

The spelling of 7881312 in words is "seven million, eight hundred eighty-one thousand, three hundred twelve".