3942191665 has 8 divisors (see below), whose sum is σ = 4738013928. Its totient is φ = 3148830720.

The previous prime is 3942191639. The next prime is 3942191683. The reversal of 3942191665 is 5661912493.

3942191665 is digitally balanced in base 2 and base 3, because in such bases it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 768897441 + 3173294224 = 27729^2 + 56332^2 .

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

It is not a de Polignac number, because 3942191665 - 2⁷ = 3942191537 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 611802 + ... + 618211.

It is an arithmetic number, because the mean of its divisors is an integer number (592251741).

Almost surely, 2^3942191665 is an apocalyptic number.

It is an amenable number.

3942191665 is a deficient number, since it is larger than the sum of its proper divisors (795822263).

3942191665 is a wasteful number, since it uses less digits than its factorization.

3942191665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1230659.

The product of its digits is 349920, while the sum is 46.

The square root of 3942191665 is about 62786.8749421406. The cubic root of 3942191665 is about 1579.7168302282.

The spelling of 3942191665 in words is "three billion, nine hundred forty-two million, one hundred ninety-one thousand, six hundred sixty-five".