812781312 has 144 divisors (see below), whose sum is σ = 2552481792. Its totient is φ = 224686080.

The previous prime is 812781311. The next prime is 812781317. The reversal of 812781312 is 213187218.

It is a super-2 number, since 2×812781312² = 1321226922272882688, which contains 22 as substring.

It is a nude number because it is divisible by every one of its digits and also a Zuckerman number because it is divisible by the product of its digits.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (812781311) 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, 164218 + ... + 169094.

It is an arithmetic number, because the mean of its divisors is an integer number (17725568).

Almost surely, 2^812781312 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 812781312, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1276240896).

812781312 is an abundant number, since it is smaller than the sum of its proper divisors (1739700480).

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

812781312 is a wasteful number, since it uses less digits than its factorization.

812781312 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4934 (or 4920 counting only the distinct ones).

The product of its digits is 5376, while the sum is 33.

The square root of 812781312 is about 28509.3197393414. The cubic root of 812781312 is about 933.2354691039.

The spelling of 812781312 in words is "eight hundred twelve million, seven hundred eighty-one thousand, three hundred twelve".