3978557165 has 8 divisors (see below), whose sum is σ = 5208293088. Its totient is φ = 2893496080.

The previous prime is 3978557161. The next prime is 3978557171. The reversal of 3978557165 is 5617558793.

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

It is not a de Polignac number, because 3978557165 - 2² = 3978557161 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 3978557165.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3978557161) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 36168647 + ... + 36168756.

It is an arithmetic number, because the mean of its divisors is an integer number (651036636).

Almost surely, 2^3978557165 is an apocalyptic number.

It is an amenable number.

3978557165 is a deficient number, since it is larger than the sum of its proper divisors (1229735923).

3978557165 is a wasteful number, since it uses less digits than its factorization.

3978557165 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 72337419.

The product of its digits is 7938000, while the sum is 56.

The square root of 3978557165 is about 63075.8049096482. The cubic root of 3978557165 is about 1584.5594366426.

The spelling of 3978557165 in words is "three billion, nine hundred seventy-eight million, five hundred fifty-seven thousand, one hundred sixty-five".