3997131665 has 8 divisors (see below), whose sum is σ = 4798738728. Its totient is φ = 3196251520.

The previous prime is 3997131653. The next prime is 3997131673. The reversal of 3997131665 is 5661317993.

It can be written as a sum of positive squares in 4 ways, for example, as 413552896 + 3583578769 = 20336^2 + 59863^2 .

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

It is not a de Polignac number, because 3997131665 - 2²⁶ = 3930022801 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 169556 + ... + 191685.

It is an arithmetic number, because the mean of its divisors is an integer number (599842341).

Almost surely, 2^3997131665 is an apocalyptic number.

It is an amenable number.

3997131665 is a deficient number, since it is larger than the sum of its proper divisors (801607063).

3997131665 is a wasteful number, since it uses less digits than its factorization.

3997131665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 363459.

The product of its digits is 918540, while the sum is 50.

The square root of 3997131665 is about 63222.8729574985. The cubic root of 3997131665 is about 1587.0215280706.

The spelling of 3997131665 in words is "three billion, nine hundred ninety-seven million, one hundred thirty-one thousand, six hundred sixty-five".