8469721 has 4 divisors (see below), whose sum is σ = 9121252. Its totient is φ = 7818192.

The previous prime is 8469709. The next prime is 8469733. The reversal of 8469721 is 1279648.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (8469709) and next prime (8469733).

It can be written as a sum of positive squares in 2 ways, for example, as 3474496 + 4995225 = 1864^2 + 2235^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-8469721 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (8469701) 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, 325746 + ... + 325771.

It is an arithmetic number, because the mean of its divisors is an integer number (2280313).

Almost surely, 2^8469721 is an apocalyptic number.

It is an amenable number.

8469721 is a deficient number, since it is larger than the sum of its proper divisors (651531).

8469721 is a wasteful number, since it uses less digits than its factorization.

8469721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 651530.

The product of its digits is 24192, while the sum is 37.

The square root of 8469721 is about 2910.2785090091. The cubic root of 8469721 is about 203.8401365149.

The spelling of 8469721 in words is "eight million, four hundred sixty-nine thousand, seven hundred twenty-one".