1291877745647 has 2 divisors, whose sum is σ = 1291877745648. Its totient is φ = 1291877745646.

The previous prime is 1291877745619. The next prime is 1291877745671. The reversal of 1291877745647 is 7465477781921.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1291877745647 - 2¹⁶ = 1291877680111 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1291877445647) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 645938872823 + 645938872824.

It is an arithmetic number, because the mean of its divisors is an integer number (645938872824).

Almost surely, 2^{1291877745647} is an apocalyptic number.

1291877745647 is a deficient number, since it is larger than the sum of its proper divisors (1).

1291877745647 is an equidigital number, since it uses as much as digits as its factorization.

1291877745647 is an evil number, because the sum of its binary digits is even.

The product of its digits is 165957120, while the sum is 68.

The spelling of 1291877745647 in words is "one trillion, two hundred ninety-one billion, eight hundred seventy-seven million, seven hundred forty-five thousand, six hundred forty-seven".