805631 has 4 divisors (see below), whose sum is σ = 810264. Its totient is φ = 801000.

The previous prime is 805589. The next prime is 805633. The reversal of 805631 is 136508.

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 805631 - 2¹⁰ = 804607 is a prime.

It is a super-2 number, since 2×805631² = 1298082616322, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 805597 and 805606.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (805633) 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, 2045 + ... + 2406.

It is an arithmetic number, because the mean of its divisors is an integer number (202566).

2⁸⁰⁵⁶³¹ is an apocalyptic number.

805631 is a deficient number, since it is larger than the sum of its proper divisors (4633).

805631 is a wasteful number, since it uses less digits than its factorization.

805631 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4632.

The product of its (nonzero) digits is 720, while the sum is 23.

The square root of 805631 is about 897.5694959166. The cubic root of 805631 is about 93.0490741886.

The spelling of 805631 in words is "eight hundred five thousand, six hundred thirty-one".