1291419761 has 2 divisors, whose sum is σ = 1291419762. Its totient is φ = 1291419760.

The previous prime is 1291419757. The next prime is 1291419791. The reversal of 1291419761 is 1679141921.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 949872400 + 341547361 = 30820^2 + 18481^2 .

It is a cyclic number.

It is not a de Polignac number, because 1291419761 - 2² = 1291419757 is a prime.

It is not a weakly prime, because it can be changed into another prime (1291419751) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 645709880 + 645709881.

It is an arithmetic number, because the mean of its divisors is an integer number (645709881).

Almost surely, 2^1291419761 is an apocalyptic number.

It is an amenable number.

1291419761 is a deficient number, since it is larger than the sum of its proper divisors (1).

1291419761 is an equidigital number, since it uses as much as digits as its factorization.

1291419761 is an evil number, because the sum of its binary digits is even.

The product of its digits is 27216, while the sum is 41.

The square root of 1291419761 is about 35936.3292644087. The cubic root of 1291419761 is about 1088.9864497439.

The spelling of 1291419761 in words is "one billion, two hundred ninety-one million, four hundred nineteen thousand, seven hundred sixty-one".