7991845 has 8 divisors (see below), whose sum is σ = 9753120. Its totient is φ = 6284880.

The previous prime is 7991839. The next prime is 7991857. The reversal of 7991845 is 5481997.

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

It is a de Polignac number, because none of the positive numbers 2^k-7991845 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 13251 + ... + 13840.

It is an arithmetic number, because the mean of its divisors is an integer number (1219140).

Almost surely, 2^7991845 is an apocalyptic number.

It is an amenable number.

7991845 is a deficient number, since it is larger than the sum of its proper divisors (1761275).

7991845 is a wasteful number, since it uses less digits than its factorization.

7991845 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27155.

The product of its digits is 90720, while the sum is 43.

The square root of 7991845 is about 2826.9851432224. The cubic root of 7991845 is about 199.9320185619.

It can be divided in two parts, 7991 and 845, that added together give a square (8836 = 94²).

The spelling of 7991845 in words is "seven million, nine hundred ninety-one thousand, eight hundred forty-five".