6587991 has 6 divisors (see below), whose sum is σ = 9516000. Its totient is φ = 4391988.

The previous prime is 6587989. The next prime is 6588007. The reversal of 6587991 is 1997856.

It is not a de Polignac number, because 6587991 - 2¹ = 6587989 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6587951) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 365991 + ... + 366008.

It is an arithmetic number, because the mean of its divisors is an integer number (1586000).

Almost surely, 2^6587991 is an apocalyptic number.

6587991 is a deficient number, since it is larger than the sum of its proper divisors (2928009).

6587991 is a wasteful number, since it uses less digits than its factorization.

6587991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 732005 (or 732002 counting only the distinct ones).

The product of its digits is 136080, while the sum is 45.

The square root of 6587991 is about 2566.7082031271. The cubic root of 6587991 is about 187.4639077196.

It can be divided in two parts, 658 and 7991, that added together give a square (8649 = 93²).

The spelling of 6587991 in words is "six million, five hundred eighty-seven thousand, nine hundred ninety-one".