7981664 has 12 divisors (see below), whose sum is σ = 15713964. Its totient is φ = 3990816.

The previous prime is 7981661. The next prime is 7981711. The reversal of 7981664 is 4661897.

It is a super-3 number, since 3×7981664³ (a number of 22 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7981661) 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 as a sum of consecutive naturals, namely, 124682 + ... + 124745.

It is an arithmetic number, because the mean of its divisors is an integer number (1309497).

Almost surely, 2^7981664 is an apocalyptic number.

It is an amenable number.

7981664 is a deficient number, since it is larger than the sum of its proper divisors (7732300).

7981664 is a wasteful number, since it uses less digits than its factorization.

7981664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 249437 (or 249429 counting only the distinct ones).

The product of its digits is 72576, while the sum is 41.

The square root of 7981664 is about 2825.1838878204. The cubic root of 7981664 is about 199.8470831119.

The spelling of 7981664 in words is "seven million, nine hundred eighty-one thousand, six hundred sixty-four".