1291312 has 60 divisors (see below), whose sum is σ = 2968560. Its totient is φ = 542080.

The previous prime is 1291271. The next prime is 1291313. The reversal of 1291312 is 2131921.

It is a self number, because there is not a number n which added to its sum of digits gives 1291312.

It is not an unprimeable number, because it can be changed into a prime (1291313) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 44514 + ... + 44542.

It is an arithmetic number, because the mean of its divisors is an integer number (49476).

2^1291312 is an apocalyptic number.

1291312 is the 928-th pentagonal number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1291312, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1484280).

1291312 is an abundant number, since it is smaller than the sum of its proper divisors (1677248).

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

1291312 is a wasteful number, since it uses less digits than its factorization.

1291312 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 82 (or 65 counting only the distinct ones).

The product of its digits is 108, while the sum is 19.

The square root of 1291312 is about 1136.3590981728. The cubic root of 1291312 is about 108.8956159171.

It can be divided in two parts, 129 and 1312, that added together give a palindrome (1441).

The spelling of 1291312 in words is "one million, two hundred ninety-one thousand, three hundred twelve".