1627809316561 has 2 divisors, whose sum is σ = 1627809316562. Its totient is φ = 1627809316560.

The previous prime is 1627809316513. The next prime is 1627809316577. The reversal of 1627809316561 is 1656139087261.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1445390635536 + 182418681025 = 1202244^2 + 427105^2 .

It is a cyclic number.

It is not a de Polignac number, because 1627809316561 - 2²³ = 1627800927953 is a prime.

It is not a weakly prime, because it can be changed into another prime (1627809316501) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 813904658280 + 813904658281.

It is an arithmetic number, because the mean of its divisors is an integer number (813904658281).

Almost surely, 2^{1627809316561} is an apocalyptic number.

It is an amenable number.

1627809316561 is a deficient number, since it is larger than the sum of its proper divisors (1).

1627809316561 is an equidigital number, since it uses as much as digits as its factorization.

1627809316561 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3265920, while the sum is 55.

The spelling of 1627809316561 in words is "one trillion, six hundred twenty-seven billion, eight hundred nine million, three hundred sixteen thousand, five hundred sixty-one".