1291500047 has 4 divisors (see below), whose sum is σ = 1367470656. Its totient is φ = 1215529440.

The previous prime is 1291499999. The next prime is 1291500079. The reversal of 1291500047 is 7400051921.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1291500047 - 2¹⁸ = 1291237903 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1291499992 and 1291500019.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1291500097) 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, 37985279 + ... + 37985312.

It is an arithmetic number, because the mean of its divisors is an integer number (341867664).

Almost surely, 2^1291500047 is an apocalyptic number.

1291500047 is a gapful number since it is divisible by the number (17) formed by its first and last digit.

1291500047 is a deficient number, since it is larger than the sum of its proper divisors (75970609).

1291500047 is an equidigital number, since it uses as much as digits as its factorization.

1291500047 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 75970608.

The product of its (nonzero) digits is 2520, while the sum is 29.

The square root of 1291500047 is about 35937.4463060468. The cubic root of 1291500047 is about 1089.0090162651.

Adding to 1291500047 its reverse (7400051921), we get a palindrome (8691551968).

The spelling of 1291500047 in words is "one billion, two hundred ninety-one million, five hundred thousand, forty-seven".