1291317541 has 4 divisors (see below), whose sum is σ = 1309505184. Its totient is φ = 1273129900.

The previous prime is 1291317523. The next prime is 1291317551. The reversal of 1291317541 is 1457131921.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 1457131921 = 7 ⋅208161703.

It is a cyclic number.

It is not a de Polignac number, because 1291317541 - 2⁷ = 1291317413 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1291317497 and 1291317506.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1291317551) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9093715 + ... + 9093856.

It is an arithmetic number, because the mean of its divisors is an integer number (327376296).

Almost surely, 2^1291317541 is an apocalyptic number.

It is an amenable number.

1291317541 is a deficient number, since it is larger than the sum of its proper divisors (18187643).

1291317541 is an equidigital number, since it uses as much as digits as its factorization.

1291317541 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18187642.

The product of its digits is 7560, while the sum is 34.

The square root of 1291317541 is about 35934.9069986274. The cubic root of 1291317541 is about 1088.9577167335.

The spelling of 1291317541 in words is "one billion, two hundred ninety-one million, three hundred seventeen thousand, five hundred forty-one".