8421945 has 16 divisors (see below), whose sum is σ = 15400320. Its totient is φ = 3849984.

The previous prime is 8421929. The next prime is 8421961. The reversal of 8421945 is 5491248.

It is an interprime number because it is at equal distance from previous prime (8421929) and next prime (8421961).

It is not a de Polignac number, because 8421945 - 2⁴ = 8421929 is a prime.

It is a Curzon 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 15 ways as a sum of consecutive naturals, for example, 40000 + ... + 40209.

It is an arithmetic number, because the mean of its divisors is an integer number (962520).

Almost surely, 2^8421945 is an apocalyptic number.

It is an amenable number.

8421945 is a deficient number, since it is larger than the sum of its proper divisors (6978375).

8421945 is a wasteful number, since it uses less digits than its factorization.

8421945 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 80224.

The product of its digits is 11520, while the sum is 33.

The square root of 8421945 is about 2902.0587519897. The cubic root of 8421945 is about 203.4561397948.

The spelling of 8421945 in words is "eight million, four hundred twenty-one thousand, nine hundred forty-five".