812778 has 8 divisors (see below), whose sum is σ = 1625568. Its totient is φ = 270924.

The previous prime is 812761. The next prime is 812807. The reversal of 812778 is 877218.

It is a sphenic number, since it is the product of 3 distinct primes.

812778 is an admirable number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 67726 + ... + 67737.

It is an arithmetic number, because the mean of its divisors is an integer number (203196).

2⁸¹²⁷⁷⁸ is an apocalyptic number.

812778 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

812778 is a wasteful number, since it uses less digits than its factorization.

812778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 135468.

The product of its digits is 6272, while the sum is 33.

The square root of 812778 is about 901.5420123322. The cubic root of 812778 is about 93.3234201489.

The spelling of 812778 in words is "eight hundred twelve thousand, seven hundred seventy-eight".