6531997128 has 16 divisors (see below), whose sum is σ = 16329992880. Its totient is φ = 2177332368.

The previous prime is 6531997127. The next prime is 6531997151. The reversal of 6531997128 is 8217991356.

It is not an unprimeable number, because it can be changed into a prime (6531997127) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 136083250 + ... + 136083297.

It is an arithmetic number, because the mean of its divisors is an integer number (1020624555).

Almost surely, 2^6531997128 is an apocalyptic number.

It is an amenable number.

6531997128 is an abundant number, since it is smaller than the sum of its proper divisors (9797995752).

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

6531997128 is a wasteful number, since it uses less digits than its factorization.

6531997128 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 272166556 (or 272166552 counting only the distinct ones).

The product of its digits is 816480, while the sum is 51.

The square root of 6531997128 is about 80820.7716369994. The cubic root of 6531997128 is about 1869.3128656374.

The spelling of 6531997128 in words is "six billion, five hundred thirty-one million, nine hundred ninety-seven thousand, one hundred twenty-eight".