3991031240 has 128 divisors (see below), whose sum is σ = 10557803520. Its totient is φ = 1329350400.

The previous prime is 3991031227. The next prime is 3991031279. The reversal of 3991031240 is 421301993.

It is a junction number, because it is equal to n+sod(n) for n = 3991031197 and 3991031206.

It is an unprimeable number.

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 31 ways as a sum of consecutive naturals, for example, 2539655 + ... + 2541225.

It is an arithmetic number, because the mean of its divisors is an integer number (82482840).

Almost surely, 2^3991031240 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 3991031240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (5278901760).

3991031240 is an abundant number, since it is smaller than the sum of its proper divisors (6566772280).

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

3991031240 is a wasteful number, since it uses less digits than its factorization.

3991031240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1843 (or 1839 counting only the distinct ones).

The product of its (nonzero) digits is 5832, while the sum is 32.

The square root of 3991031240 is about 63174.6091400651. The cubic root of 3991031240 is about 1586.2137458820.

The spelling of 3991031240 in words is "three billion, nine hundred ninety-one million, thirty-one thousand, two hundred forty".