812864 has 28 divisors (see below), whose sum is σ = 1738884. Its totient is φ = 374784.

The previous prime is 812857. The next prime is 812869. The reversal of 812864 is 468218.

It can be written as a sum of positive squares in 2 ways, for example, as 462400 + 350464 = 680^2 + 592^2 .

It is a hoax number, since the sum of its digits (29) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (812869) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 344 + ... + 1320.

It is an arithmetic number, because the mean of its divisors is an integer number (62103).

2⁸¹²⁸⁶⁴ 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 812864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (869442).

812864 is an abundant number, since it is smaller than the sum of its proper divisors (926020).

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

812864 is a wasteful number, since it uses less digits than its factorization.

812864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1002 (or 992 counting only the distinct ones).

The product of its digits is 3072, while the sum is 29.

The square root of 812864 is about 901.5897071285. The cubic root of 812864 is about 93.3267115484.

It can be divided in two parts, 8128 and 64, that added together give a 13-th power (8192 = 2¹³).

The spelling of 812864 in words is "eight hundred twelve thousand, eight hundred sixty-four".