3991161550 has 24 divisors (see below), whose sum is σ = 7429118256. Its totient is φ = 1595269440.

The previous prime is 3991161539. The next prime is 3991161589. The reversal of 3991161550 is 551611993.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 39154 + ... + 97546.

It is an arithmetic number, because the mean of its divisors is an integer number (309546594).

Almost surely, 2^3991161550 is an apocalyptic number.

3991161550 is a deficient number, since it is larger than the sum of its proper divisors (3437956706).

3991161550 is a wasteful number, since it uses less digits than its factorization.

3991161550 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 59772 (or 59767 counting only the distinct ones).

The product of its (nonzero) digits is 36450, while the sum is 40.

The square root of 3991161550 is about 63175.6404795393. The cubic root of 3991161550 is about 1586.2310093620.

The spelling of 3991161550 in words is "three billion, nine hundred ninety-one million, one hundred sixty-one thousand, five hundred fifty".