985721 has 4 divisors (see below), whose sum is σ = 1075344. Its totient is φ = 896100.

The previous prime is 985709. The next prime is 985723. The reversal of 985721 is 127589.

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 985721 - 2⁶ = 985657 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 985721.

It is not an unprimeable number, because it can be changed into a prime (985723) 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, 44795 + ... + 44816.

It is an arithmetic number, because the mean of its divisors is an integer number (268836).

2⁹⁸⁵⁷²¹ is an apocalyptic number.

It is an amenable number.

985721 is a deficient number, since it is larger than the sum of its proper divisors (89623).

985721 is a wasteful number, since it uses less digits than its factorization.

985721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 89622.

The product of its digits is 5040, while the sum is 32.

The square root of 985721 is about 992.8348301707. The cubic root of 985721 is about 99.5217497465.

The spelling of 985721 in words is "nine hundred eighty-five thousand, seven hundred twenty-one".