367991 has 4 divisors (see below), whose sum is σ = 396312. Its totient is φ = 339672.

The previous prime is 367957. The next prime is 368021. The reversal of 367991 is 199763.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 199763 = 37 ⋅5399.

It is a cyclic number.

It is not a de Polignac number, because 367991 - 2¹⁰ = 366967 is a prime.

It is a Duffinian number.

It is a nialpdrome in base 13.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (367391) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 14141 + ... + 14166.

It is an arithmetic number, because the mean of its divisors is an integer number (99078).

2³⁶⁷⁹⁹¹ is an apocalyptic number.

367991 is a deficient number, since it is larger than the sum of its proper divisors (28321).

367991 is a wasteful number, since it uses less digits than its factorization.

367991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28320.

The product of its digits is 10206, while the sum is 35.

The square root of 367991 is about 606.6226174484. The cubic root of 367991 is about 71.6603732230.

The spelling of 367991 in words is "three hundred sixty-seven thousand, nine hundred ninety-one".