1291204471 has 2 divisors, whose sum is σ = 1291204472. Its totient is φ = 1291204470.

The previous prime is 1291204463. The next prime is 1291204493. The reversal of 1291204471 is 1744021921.

It is a weak prime.

It is an emirp because it is prime and its reverse (1744021921) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1291204471 - 2³ = 1291204463 is a prime.

It is a super-3 number, since 3×1291204471³ (a number of 28 digits) contains 333 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1291204571) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 645602235 + 645602236.

It is an arithmetic number, because the mean of its divisors is an integer number (645602236).

Almost surely, 2^1291204471 is an apocalyptic number.

1291204471 is a deficient number, since it is larger than the sum of its proper divisors (1).

1291204471 is an equidigital number, since it uses as much as digits as its factorization.

1291204471 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4032, while the sum is 31.

The square root of 1291204471 is about 35933.3337028448. Note that the first 3 decimals coincide. The cubic root of 1291204471 is about 1088.9259321314.

The spelling of 1291204471 in words is "one billion, two hundred ninety-one million, two hundred four thousand, four hundred seventy-one".