872921 has 4 divisors (see below), whose sum is σ = 997632. Its totient is φ = 748212.

The previous prime is 872863. The next prime is 872923. The reversal of 872921 is 129278.

It is a happy number.

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 a de Polignac number, because none of the positive numbers 2^k-872921 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian number.

It is a plaindrome in base 15.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 872921.

It is not an unprimeable number, because it can be changed into a prime (872923) 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, 62345 + ... + 62358.

It is an arithmetic number, because the mean of its divisors is an integer number (249408).

2⁸⁷²⁹²¹ is an apocalyptic number.

It is an amenable number.

872921 is a deficient number, since it is larger than the sum of its proper divisors (124711).

872921 is a wasteful number, since it uses less digits than its factorization.

872921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 124710.

The product of its digits is 2016, while the sum is 29.

The square root of 872921 is about 934.3024135685. The cubic root of 872921 is about 95.5707469888.

The spelling of 872921 in words is "eight hundred seventy-two thousand, nine hundred twenty-one".