996581 has 4 divisors (see below), whose sum is σ = 1008672. Its totient is φ = 984492.

The previous prime is 996571. The next prime is 996599. The reversal of 996581 is 185699.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 996581 - 2¹⁴ = 980197 is a prime.

It is a super-2 number, since 2×996581² = 1986347379122, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 996581.

It is not an unprimeable number, because it can be changed into a prime (996511) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5921 + ... + 6086.

It is an arithmetic number, because the mean of its divisors is an integer number (252168).

2⁹⁹⁶⁵⁸¹ is an apocalyptic number.

It is an amenable number.

996581 is a deficient number, since it is larger than the sum of its proper divisors (12091).

996581 is a wasteful number, since it uses less digits than its factorization.

996581 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12090.

The product of its digits is 19440, while the sum is 38.

The square root of 996581 is about 998.2890363016. The cubic root of 996581 is about 99.8859032021.

The spelling of 996581 in words is "nine hundred ninety-six thousand, five hundred eighty-one".