3975165581 has 4 divisors (see below), whose sum is σ = 4011635100. Its totient is φ = 3938696064.

The previous prime is 3975165553. The next prime is 3975165611. The reversal of 3975165581 is 1855615793.

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 1863303556 + 2111862025 = 43166^2 + 45955^2 .

It is a cyclic number.

It is not a de Polignac number, because 3975165581 - 2¹⁴ = 3975149197 is a prime.

It is a super-2 number, since 2×3975165581² = 31603882792734135122, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3975161581) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 18234596 + ... + 18234813.

It is an arithmetic number, because the mean of its divisors is an integer number (1002908775).

Almost surely, 2^3975165581 is an apocalyptic number.

It is an amenable number.

3975165581 is a deficient number, since it is larger than the sum of its proper divisors (36469519).

3975165581 is a wasteful number, since it uses less digits than its factorization.

3975165581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36469518.

The product of its digits is 1134000, while the sum is 50.

The square root of 3975165581 is about 63048.9141936640. The cubic root of 3975165581 is about 1584.1090477176.

The spelling of 3975165581 in words is "three billion, nine hundred seventy-five million, one hundred sixty-five thousand, five hundred eighty-one".