140991 has 4 divisors (see below), whose sum is σ = 187992. Its totient is φ = 93992.

The previous prime is 140989. The next prime is 141023. The reversal of 140991 is 199041.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 199041 = 3 ⋅66347.

It is a cyclic number.

It is not a de Polignac number, because 140991 - 2¹ = 140989 is a prime.

It is a D-number.

It is a plaindrome in base 16.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (140191) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 23496 + ... + 23501.

It is an arithmetic number, because the mean of its divisors is an integer number (46998).

2¹⁴⁰⁹⁹¹ is an apocalyptic number.

140991 is a deficient number, since it is larger than the sum of its proper divisors (47001).

140991 is an equidigital number, since it uses as much as digits as its factorization.

140991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 47000.

The product of its (nonzero) digits is 324, while the sum is 24.

The square root of 140991 is about 375.4876828872. The cubic root of 140991 is about 52.0471712002.

The spelling of 140991 in words is "one hundred forty thousand, nine hundred ninety-one".