1277916791 has 2 divisors, whose sum is σ = 1277916792. Its totient is φ = 1277916790.

The previous prime is 1277916671. The next prime is 1277916803. The reversal of 1277916791 is 1976197721.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1277916791 - 2¹⁰ = 1277915767 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1277916091) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 638958395 + 638958396.

It is an arithmetic number, because the mean of its divisors is an integer number (638958396).

Almost surely, 2^1277916791 is an apocalyptic number.

1277916791 is a deficient number, since it is larger than the sum of its proper divisors (1).

1277916791 is an equidigital number, since it uses as much as digits as its factorization.

1277916791 is an evil number, because the sum of its binary digits is even.

The product of its digits is 333396, while the sum is 50.

The square root of 1277916791 is about 35747.9620538011. The cubic root of 1277916791 is about 1085.1776956304.

The spelling of 1277916791 in words is "one billion, two hundred seventy-seven million, nine hundred sixteen thousand, seven hundred ninety-one".