812987 has 4 divisors (see below), whose sum is σ = 929136. Its totient is φ = 696840.

The previous prime is 812969. The next prime is 813013. The reversal of 812987 is 789218.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 812987 - 2⁸ = 812731 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (812387) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 58064 + ... + 58077.

It is an arithmetic number, because the mean of its divisors is an integer number (232284).

2⁸¹²⁹⁸⁷ is an apocalyptic number.

812987 is a deficient number, since it is larger than the sum of its proper divisors (116149).

812987 is a wasteful number, since it uses less digits than its factorization.

812987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 116148.

The product of its digits is 8064, while the sum is 35.

The square root of 812987 is about 901.6579173944. The cubic root of 812987 is about 93.3314186115.

The spelling of 812987 in words is "eight hundred twelve thousand, nine hundred eighty-seven".