1291478471 has 2 divisors, whose sum is σ = 1291478472. Its totient is φ = 1291478470.
The previous prime is 1291478459. The next prime is 1291478473. The reversal of 1291478471 is 1748741921.
It is a strong prime.
It is an emirp because it is prime and its reverse (1748741921) is a distict prime.
It is a cyclic number.
It is not a de Polignac number, because 1291478471 - 218 = 1291216327 is a prime.
It is a super-3 number, since 3×12914784713 (a number of 28 digits) contains 333 as substring.
Together with 1291478473, it forms a pair of twin primes.
It is a Chen prime.
It is a congruent number.
It is not a weakly prime, because it can be changed into another prime (1291478473) by changing a digit.
It is a polite number, since it can be written as a sum of consecutive naturals, namely, 645739235 + 645739236.
It is an arithmetic number, because the mean of its divisors is an integer number (645739236).
Almost surely, 21291478471 is an apocalyptic number.
1291478471 is a deficient number, since it is larger than the sum of its proper divisors (1).
1291478471 is an equidigital number, since it uses as much as digits as its factorization.
1291478471 is an evil number, because the sum of its binary digits is even.
The product of its digits is 112896, while the sum is 44.
The square root of 1291478471 is about 35937.1461165185. The cubic root of 1291478471 is about 1089.0029518469.
The spelling of 1291478471 in words is "one billion, two hundred ninety-one million, four hundred seventy-eight thousand, four hundred seventy-one".
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