1231291 has 8 divisors (see below), whose sum is σ = 1268064. Its totient is φ = 1195200.

The previous prime is 1231283. The next prime is 1231301. The reversal of 1231291 is 1921321.

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 1231291 - 2³ = 1231283 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1231201) 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, 7290 + ... + 7456.

It is an arithmetic number, because the mean of its divisors is an integer number (158508).

2^1231291 is an apocalyptic number.

1231291 is a deficient number, since it is larger than the sum of its proper divisors (36773).

1231291 is a wasteful number, since it uses less digits than its factorization.

1231291 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 341.

The product of its digits is 108, while the sum is 19.

The square root of 1231291 is about 1109.6355257471. The cubic root of 1231291 is about 107.1815997880.

It can be divided in two parts, 12312 and 91, that added together give a triangular number (12403 = T₁₅₇).

The spelling of 1231291 in words is "one million, two hundred thirty-one thousand, two hundred ninety-one".