1251166688647 has 2 divisors, whose sum is σ = 1251166688648. Its totient is φ = 1251166688646.

The previous prime is 1251166688567. The next prime is 1251166688677. The reversal of 1251166688647 is 7468866611521.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1251166688647 - 2¹⁹ = 1251166164359 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1251166688677) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 625583344323 + 625583344324.

It is an arithmetic number, because the mean of its divisors is an integer number (625583344324).

Almost surely, 2^{1251166688647} is an apocalyptic number.

1251166688647 is a deficient number, since it is larger than the sum of its proper divisors (1).

1251166688647 is an equidigital number, since it uses as much as digits as its factorization.

1251166688647 is an evil number, because the sum of its binary digits is even.

The product of its digits is 23224320, while the sum is 61.

The spelling of 1251166688647 in words is "one trillion, two hundred fifty-one billion, one hundred sixty-six million, six hundred eighty-eight thousand, six hundred forty-seven".