6531136639 has 2 divisors, whose sum is σ = 6531136640. Its totient is φ = 6531136638.

The previous prime is 6531136621. The next prime is 6531136693. The reversal of 6531136639 is 9366311356.

Together with next prime (6531136693) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 6531136639 - 2¹³ = 6531128447 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 6531136595 and 6531136604.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6531136939) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3265568319 + 3265568320.

It is an arithmetic number, because the mean of its divisors is an integer number (3265568320).

Almost surely, 2^6531136639 is an apocalyptic number.

6531136639 is a deficient number, since it is larger than the sum of its proper divisors (1).

6531136639 is an equidigital number, since it uses as much as digits as its factorization.

6531136639 is an evil number, because the sum of its binary digits is even.

The product of its digits is 262440, while the sum is 43.

The square root of 6531136639 is about 80815.4480220211. The cubic root of 6531136639 is about 1869.2307777367.

The spelling of 6531136639 in words is "six billion, five hundred thirty-one million, one hundred thirty-six thousand, six hundred thirty-nine".