3991319880 has 64 divisors (see below), whose sum is σ = 12386865600. Its totient is φ = 1027649280.

The previous prime is 3991319861. The next prime is 3991319887. The reversal of 3991319880 is 889131993.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (3991319887) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 569986 + ... + 576945.

It is an arithmetic number, because the mean of its divisors is an integer number (193544775).

Almost surely, 2^3991319880 is an apocalyptic number.

3991319880 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

3991319880 is an abundant number, since it is smaller than the sum of its proper divisors (8395545720).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

3991319880 is a wasteful number, since it uses less digits than its factorization.

3991319880 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1146974 (or 1146970 counting only the distinct ones).

The product of its (nonzero) digits is 419904, while the sum is 51.

The square root of 3991319880 is about 63176.8935608582. The cubic root of 3991319880 is about 1586.2519844283.

The spelling of 3991319880 in words is "three billion, nine hundred ninety-one million, three hundred nineteen thousand, eight hundred eighty".