7981645 has 16 divisors (see below), whose sum is σ = 11063808. Its totient is φ = 5414400.

The previous prime is 7981639. The next prime is 7981661. The reversal of 7981645 is 5461897.

It is not a de Polignac number, because 7981645 - 2¹³ = 7973453 is a prime.

It is a super-3 number, since 3×7981645³ (a number of 22 digits) contains 333 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 7981598 and 7981607.

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 15 ways as a sum of consecutive naturals, for example, 2220 + ... + 4570.

It is an arithmetic number, because the mean of its divisors is an integer number (691488).

Almost surely, 2^7981645 is an apocalyptic number.

It is an amenable number.

7981645 is a deficient number, since it is larger than the sum of its proper divisors (3082163).

7981645 is a wasteful number, since it uses less digits than its factorization.

7981645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2460.

The product of its digits is 60480, while the sum is 40.

The square root of 7981645 is about 2825.1805252054. The cubic root of 7981645 is about 199.8469245361.

The spelling of 7981645 in words is "seven million, nine hundred eighty-one thousand, six hundred forty-five".