3991618320 has 40 divisors (see below), whose sum is σ = 12374017536. Its totient is φ = 1064431488.

The previous prime is 3991618307. The next prime is 3991618333. The reversal of 3991618320 is 238161993.

3991618320 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (3991618307) and next prime (3991618333).

It is a tau number, because it is divible by the number of its divisors (40).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8315632 + ... + 8316111.

Almost surely, 2^3991618320 is an apocalyptic number.

3991618320 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

3991618320 is an abundant number, since it is smaller than the sum of its proper divisors (8382399216).

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

3991618320 is a wasteful number, since it uses less digits than its factorization.

3991618320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16631759 (or 16631753 counting only the distinct ones).

The product of its (nonzero) digits is 69984, while the sum is 42.

The square root of 3991618320 is about 63179.2554562018. The cubic root of 3991618320 is about 1586.2915193239.

The spelling of 3991618320 in words is "three billion, nine hundred ninety-one million, six hundred eighteen thousand, three hundred twenty".