1291428917 has 8 divisors (see below), whose sum is σ = 1388323200. Its totient is φ = 1197427104.

The previous prime is 1291428889. The next prime is 1291428937. The reversal of 1291428917 is 7198241921.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1291428917 - 2⁸ = 1291428661 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1291428937) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 722192 + ... + 723977.

It is an arithmetic number, because the mean of its divisors is an integer number (173540400).

Almost surely, 2^1291428917 is an apocalyptic number.

It is an amenable number.

1291428917 is a deficient number, since it is larger than the sum of its proper divisors (96894283).

1291428917 is a wasteful number, since it uses less digits than its factorization.

1291428917 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1446235.

The product of its digits is 72576, while the sum is 44.

The square root of 1291428917 is about 35936.4566561591. The cubic root of 1291428917 is about 1088.9890233291.

The spelling of 1291428917 in words is "one billion, two hundred ninety-one million, four hundred twenty-eight thousand, nine hundred seventeen".