1367991 has 12 divisors (see below), whose sum is σ = 1997632. Its totient is φ = 902016.

The previous prime is 1367987. The next prime is 1368013. The reversal of 1367991 is 1997631.

It is not a de Polignac number, because 1367991 - 2² = 1367987 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 (1367921) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 90 + ... + 1656.

2^1367991 is an apocalyptic number.

1367991 is a deficient number, since it is larger than the sum of its proper divisors (629641).

1367991 is a wasteful number, since it uses less digits than its factorization.

1367991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1670 (or 1667 counting only the distinct ones).

The product of its digits is 10206, while the sum is 36.

The square root of 1367991 is about 1169.6114739519. The cubic root of 1367991 is about 111.0097386148.

The spelling of 1367991 in words is "one million, three hundred sixty-seven thousand, nine hundred ninety-one".