812155 has 16 divisors (see below), whose sum is σ = 1048320. Its totient is φ = 602208.

The previous prime is 812137. The next prime is 812167. The reversal of 812155 is 551218.

It is a cyclic number.

It is not a de Polignac number, because 812155 - 2¹³ = 803963 is a prime.

It is an Ulam 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 15 ways as a sum of consecutive naturals, for example, 7834 + ... + 7936.

It is an arithmetic number, because the mean of its divisors is an integer number (65520).

2⁸¹²¹⁵⁵ is an apocalyptic number.

812155 is a deficient number, since it is larger than the sum of its proper divisors (236165).

812155 is a wasteful number, since it uses less digits than its factorization.

812155 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 210.

The product of its digits is 400, while the sum is 22.

The square root of 812155 is about 901.1964269792. The cubic root of 812155 is about 93.2995697035.

The spelling of 812155 in words is "eight hundred twelve thousand, one hundred fifty-five".