3991940897 has 16 divisors (see below), whose sum is σ = 4728213504. Its totient is φ = 3298050000.

The previous prime is 3991940891. The next prime is 3991940929. The reversal of 3991940897 is 7980491993.

It is not a de Polignac number, because 3991940897 - 2¹⁸ = 3991678753 is a prime.

It is not an unprimeable number, because it can be changed into a prime (3991940891) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 17822 + ... + 91112.

It is an arithmetic number, because the mean of its divisors is an integer number (295513344).

Almost surely, 2^3991940897 is an apocalyptic number.

It is an amenable number.

3991940897 is a deficient number, since it is larger than the sum of its proper divisors (736272607).

3991940897 is a wasteful number, since it uses less digits than its factorization.

3991940897 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 73580.

The product of its (nonzero) digits is 4408992, while the sum is 59.

The square root of 3991940897 is about 63181.8082758004. The cubic root of 3991940897 is about 1586.3342494762.

The spelling of 3991940897 in words is "three billion, nine hundred ninety-one million, nine hundred forty thousand, eight hundred ninety-seven".