2991491538 has 16 divisors (see below), whose sum is σ = 6837695040. Its totient is φ = 854711856.

The previous prime is 2991491533. The next prime is 2991491557. The reversal of 2991491538 is 8351941992.

It is not an unprimeable number, because it can be changed into a prime (2991491533) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 35612953 + ... + 35613036.

It is an arithmetic number, because the mean of its divisors is an integer number (427355940).

Almost surely, 2^2991491538 is an apocalyptic number.

2991491538 is an abundant number, since it is smaller than the sum of its proper divisors (3846203502).

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

2991491538 is a wasteful number, since it uses less digits than its factorization.

2991491538 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 71226001.

The product of its digits is 699840, while the sum is 51.

The square root of 2991491538 is about 54694.5293242386. The cubic root of 2991491538 is about 1440.8847986296.

The spelling of 2991491538 in words is "two billion, nine hundred ninety-one million, four hundred ninety-one thousand, five hundred thirty-eight".