3991718 has 8 divisors (see below), whose sum is σ = 6085920. Its totient is φ = 1963080.

The previous prime is 3991717. The next prime is 3991723. The reversal of 3991718 is 8171993.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3991711) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16238 + ... + 16481.

It is an arithmetic number, because the mean of its divisors is an integer number (760740).

Almost surely, 2^3991718 is an apocalyptic number.

3991718 is a deficient number, since it is larger than the sum of its proper divisors (2094202).

3991718 is a wasteful number, since it uses less digits than its factorization.

3991718 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32782.

The product of its digits is 13608, while the sum is 38.

The square root of 3991718 is about 1997.9284271465. The cubic root of 3991718 is about 158.6304723678.

The spelling of 3991718 in words is "three million, nine hundred ninety-one thousand, seven hundred eighteen".