8421745 has 12 divisors (see below), whose sum is σ = 10498140. Its totient is φ = 6478080.

The previous prime is 8421737. The next prime is 8421757. The reversal of 8421745 is 5471248.

It can be written as a sum of positive squares in 6 ways, for example, as 350464 + 8071281 = 592^2 + 2841^2 .

It is not a de Polignac number, because 8421745 - 2³ = 8421737 is a prime.

It is a d-powerful number, because it can be written as 8⁵ + 4 + 2²³ + 1 + 7³ + 4² + 5 .

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 34825 + ... + 35065.

It is an arithmetic number, because the mean of its divisors is an integer number (874845).

Almost surely, 2^8421745 is an apocalyptic number.

It is an amenable number.

8421745 is a deficient number, since it is larger than the sum of its proper divisors (2076395).

8421745 is an equidigital number, since it uses as much as digits as its factorization.

8421745 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 516 (or 275 counting only the distinct ones).

The product of its digits is 8960, while the sum is 31.

The square root of 8421745 is about 2902.0242934889. The cubic root of 8421745 is about 203.4545292583.

The spelling of 8421745 in words is "eight million, four hundred twenty-one thousand, seven hundred forty-five".