992721 has 4 divisors (see below), whose sum is σ = 1323632. Its totient is φ = 661812.

The previous prime is 992707. The next prime is 992723. The reversal of 992721 is 127299.

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, and also an emirpimes, since its reverse is a distinct semiprime: 127299 = 3 ⋅42433.

It is not a de Polignac number, because 992721 - 2⁵ = 992689 is a prime.

It is a D-number.

It is a Duffinian number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 992721.

It is not an unprimeable number, because it can be changed into a prime (992723) 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, 165451 + ... + 165456.

It is an arithmetic number, because the mean of its divisors is an integer number (330908).

2⁹⁹²⁷²¹ is an apocalyptic number.

It is an amenable number.

992721 is a deficient number, since it is larger than the sum of its proper divisors (330911).

992721 is a wasteful number, since it uses less digits than its factorization.

992721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 330910.

The product of its digits is 2268, while the sum is 30.

The square root of 992721 is about 996.3538528053. The cubic root of 992721 is about 99.7567755650.

The spelling of 992721 in words is "nine hundred ninety-two thousand, seven hundred twenty-one".