5999999991 has 8 divisors (see below), whose sum is σ = 8150943600. Its totient is φ = 3924528192.

The previous prime is 5999999989. The next prime is 6000000001. The reversal of 5999999991 is 1999999995.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 5999999991 - 2¹ = 5999999989 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (5999999591) 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, 18867766 + ... + 18868083.

It is an arithmetic number, because the mean of its divisors is an integer number (1018867950).

Almost surely, 2^5999999991 is an apocalyptic number.

5999999991 is a deficient number, since it is larger than the sum of its proper divisors (2150943609).

5999999991 is a wasteful number, since it uses less digits than its factorization.

5999999991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 37735905.

The product of its digits is 215233605, while the sum is 78.

The square root of 5999999991 is about 77459.6668660536. Note that the first 3 decimals coincide. The cubic root of 5999999991 is about 1817.1205919236.

The spelling of 5999999991 in words is "five billion, nine hundred ninety-nine million, nine hundred ninety-nine thousand, nine hundred ninety-one".