6631545327991 has 8 divisors (see below), whose sum is σ = 6682696438064. Its totient is φ = 6580567319040.

The previous prime is 6631545327977. The next prime is 6631545328027. The reversal of 6631545327991 is 1997235451366.

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

It is not a de Polignac number, because 6631545327991 - 2⁹ = 6631545327479 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6631545327941) 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, 43198365 + ... + 43351606.

It is an arithmetic number, because the mean of its divisors is an integer number (835337054758).

Almost surely, 2^{6631545327991} is an apocalyptic number.

6631545327991 is a deficient number, since it is larger than the sum of its proper divisors (51151110073).

6631545327991 is a wasteful number, since it uses less digits than its factorization.

6631545327991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 86550561.

The product of its digits is 36741600, while the sum is 61.

The spelling of 6631545327991 in words is "six trillion, six hundred thirty-one billion, five hundred forty-five million, three hundred twenty-seven thousand, nine hundred ninety-one".