691675660547 has 2 divisors, whose sum is σ = 691675660548. Its totient is φ = 691675660546.

The previous prime is 691675660541. The next prime is 691675660549. The reversal of 691675660547 is 745066576196.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 691675660547 - 2⁶ = 691675660483 is a prime.

Together with 691675660549, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 691675660547.

It is not a weakly prime, because it can be changed into another prime (691675660541) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 345837830273 + 345837830274.

It is an arithmetic number, because the mean of its divisors is an integer number (345837830274).

Almost surely, 2^691675660547 is an apocalyptic number.

691675660547 is a deficient number, since it is larger than the sum of its proper divisors (1).

691675660547 is an equidigital number, since it uses as much as digits as its factorization.

691675660547 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 57153600, while the sum is 62.

The spelling of 691675660547 in words is "six hundred ninety-one billion, six hundred seventy-five million, six hundred sixty thousand, five hundred forty-seven".