1291971 has 8 divisors (see below), whose sum is σ = 1736704. Its totient is φ = 854280.

The previous prime is 1291967. The next prime is 1291991. The reversal of 1291971 is 1791921.

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

It is not a de Polignac number, because 1291971 - 2² = 1291967 is a prime.

It is a Duffinian number.

1291971 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (1291931) 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, 1315 + ... + 2076.

It is an arithmetic number, because the mean of its divisors is an integer number (217088).

2^1291971 is an apocalyptic number.

1291971 is a deficient number, since it is larger than the sum of its proper divisors (444733).

1291971 is a wasteful number, since it uses less digits than its factorization.

1291971 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3521.

The product of its digits is 1134, while the sum is 30.

The square root of 1291971 is about 1136.6490223459. The cubic root of 1291971 is about 108.9141371335.

The spelling of 1291971 in words is "one million, two hundred ninety-one thousand, nine hundred seventy-one".