3991394 has 16 divisors (see below), whose sum is σ = 6562080. Its totient is φ = 1805760.

The previous prime is 3991369. The next prime is 3991399. The reversal of 3991394 is 4931993.

It is a Curzon number.

It is a nialpdrome in base 13.

It is not an unprimeable number, because it can be changed into a prime (3991399) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9002 + ... + 9434.

It is an arithmetic number, because the mean of its divisors is an integer number (410130).

Almost surely, 2^3991394 is an apocalyptic number.

3991394 is a deficient number, since it is larger than the sum of its proper divisors (2570686).

3991394 is a wasteful number, since it uses less digits than its factorization.

3991394 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 865.

The product of its digits is 26244, while the sum is 38.

The square root of 3991394 is about 1997.8473415154. The cubic root of 3991394 is about 158.6261803425.

The spelling of 3991394 in words is "three million, nine hundred ninety-one thousand, three hundred ninety-four".