825631 has 4 divisors (see below), whose sum is σ = 861552. Its totient is φ = 789712.

The previous prime is 825613. The next prime is 825637. The reversal of 825631 is 136528.

825631 = T₁₆₆ + T₁₆₇ + ... + T₂₁₁.

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 825631 - 2¹⁷ = 694559 is a prime.

It is a super-2 number, since 2×825631² = 1363333096322, which contains 22 as substring.

It is a d-powerful number, because it can be written as 8⁶ + 2¹⁴ + 6² + 5⁶ + 3¹² + 1 .

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 825596 and 825605.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (825637) by changing a digit.

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, 17926 + ... + 17971.

It is an arithmetic number, because the mean of its divisors is an integer number (215388).

2⁸²⁵⁶³¹ is an apocalyptic number.

825631 is a deficient number, since it is larger than the sum of its proper divisors (35921).

825631 is a wasteful number, since it uses less digits than its factorization.

825631 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35920.

The product of its digits is 1440, while the sum is 25.

The square root of 825631 is about 908.6423939042. The cubic root of 825631 is about 93.8127781005.

The spelling of 825631 in words is "eight hundred twenty-five thousand, six hundred thirty-one".