6487667521 has 2 divisors, whose sum is σ = 6487667522. Its totient is φ = 6487667520.

The previous prime is 6487667497. The next prime is 6487667561. The reversal of 6487667521 is 1257667846.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 5839252225 + 648415296 = 76415^2 + 25464^2 .

It is a cyclic number.

It is not a de Polignac number, because 6487667521 - 2¹⁵ = 6487634753 is a prime.

It is not a weakly prime, because it can be changed into another prime (6487667561) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3243833760 + 3243833761.

It is an arithmetic number, because the mean of its divisors is an integer number (3243833761).

Almost surely, 2^6487667521 is an apocalyptic number.

It is an amenable number.

6487667521 is a deficient number, since it is larger than the sum of its proper divisors (1).

6487667521 is an equidigital number, since it uses as much as digits as its factorization.

6487667521 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3386880, while the sum is 52.

The square root of 6487667521 is about 80546.0583827663. The cubic root of 6487667521 is about 1865.0745461557.

The spelling of 6487667521 in words is "six billion, four hundred eighty-seven million, six hundred sixty-seven thousand, five hundred twenty-one".