8425721 has 8 divisors (see below), whose sum is σ = 9076320. Its totient is φ = 7795872.

The previous prime is 8425717. The next prime is 8425741. The reversal of 8425721 is 1275248.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 8425721 - 2² = 8425717 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (8425741) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4340 + ... + 5973.

It is an arithmetic number, because the mean of its divisors is an integer number (1134540).

Almost surely, 2^8425721 is an apocalyptic number.

It is an amenable number.

8425721 is a deficient number, since it is larger than the sum of its proper divisors (650599).

8425721 is a wasteful number, since it uses less digits than its factorization.

8425721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10375.

The product of its digits is 4480, while the sum is 29.

The square root of 8425721 is about 2902.7092517164. The cubic root of 8425721 is about 203.4865419405.

The spelling of 8425721 in words is "eight million, four hundred twenty-five thousand, seven hundred twenty-one".