7981745 has 4 divisors (see below), whose sum is σ = 9578100. Its totient is φ = 6385392.

The previous prime is 7981717. The next prime is 7981783. The reversal of 7981745 is 5471897.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1366561 + 6615184 = 1169^2 + 2572^2 .

It is a cyclic number.

It is not a de Polignac number, because 7981745 - 2¹² = 7977649 is a prime.

It is a Curzon number.

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 3 ways as a sum of consecutive naturals, for example, 798170 + ... + 798179.

It is an arithmetic number, because the mean of its divisors is an integer number (2394525).

Almost surely, 2^7981745 is an apocalyptic number.

It is an amenable number.

7981745 is a deficient number, since it is larger than the sum of its proper divisors (1596355).

7981745 is a wasteful number, since it uses less digits than its factorization.

7981745 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1596354.

The product of its digits is 70560, while the sum is 41.

The square root of 7981745 is about 2825.1982231341. The cubic root of 7981745 is about 199.8477591430.

The spelling of 7981745 in words is "seven million, nine hundred eighty-one thousand, seven hundred forty-five".