3991519540 has 12 divisors (see below), whose sum is σ = 8382191076. Its totient is φ = 1596607808.

The previous prime is 3991519537. The next prime is 3991519579. The reversal of 3991519540 is 459151993.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 914820516 + 3076699024 = 30246^2 + 55468^2 .

It is a congruent number.

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 3 ways as a sum of consecutive naturals, for example, 99787969 + ... + 99788008.

It is an arithmetic number, because the mean of its divisors is an integer number (698515923).

Almost surely, 2^3991519540 is an apocalyptic number.

It is an amenable number.

3991519540 is an abundant number, since it is smaller than the sum of its proper divisors (4390671536).

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

3991519540 is a wasteful number, since it uses less digits than its factorization.

3991519540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 199575986 (or 199575984 counting only the distinct ones).

The product of its (nonzero) digits is 218700, while the sum is 46.

The square root of 3991519540 is about 63178.4737074266. The cubic root of 3991519540 is about 1586.2784339738.

The spelling of 3991519540 in words is "three billion, nine hundred ninety-one million, five hundred nineteen thousand, five hundred forty".