1279547491 has 2 divisors, whose sum is σ = 1279547492. Its totient is φ = 1279547490.

The previous prime is 1279547459. The next prime is 1279547497. The reversal of 1279547491 is 1947459721.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1279547491 - 2⁵ = 1279547459 is a prime.

It is not a weakly prime, because it can be changed into another prime (1279547497) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 639773745 + 639773746.

It is an arithmetic number, because the mean of its divisors is an integer number (639773746).

Almost surely, 2^1279547491 is an apocalyptic number.

1279547491 is a deficient number, since it is larger than the sum of its proper divisors (1).

1279547491 is an equidigital number, since it uses as much as digits as its factorization.

1279547491 is an evil number, because the sum of its binary digits is even.

The product of its digits is 635040, while the sum is 49.

The square root of 1279547491 is about 35770.7630754503. The cubic root of 1279547491 is about 1085.6390838074.

The spelling of 1279547491 in words is "one billion, two hundred seventy-nine million, five hundred forty-seven thousand, four hundred ninety-one".