137891 has 4 divisors (see below), whose sum is σ = 148512. Its totient is φ = 127272.

The previous prime is 137873. The next prime is 137909. The reversal of 137891 is 198731.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 198731 = 13 ⋅15287.

It is an interprime number because it is at equal distance from previous prime (137873) and next prime (137909).

It is a cyclic number.

It is not a de Polignac number, because 137891 - 2⁶ = 137827 is a prime.

It is not an unprimeable number, because it can be changed into a prime (137831) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5291 + ... + 5316.

It is an arithmetic number, because the mean of its divisors is an integer number (37128).

2¹³⁷⁸⁹¹ is an apocalyptic number.

137891 is a deficient number, since it is larger than the sum of its proper divisors (10621).

137891 is a wasteful number, since it uses less digits than its factorization.

137891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10620.

The product of its digits is 1512, while the sum is 29.

The square root of 137891 is about 371.3367743707. The cubic root of 137891 is about 51.6628832933.

The spelling of 137891 in words is "one hundred thirty-seven thousand, eight hundred ninety-one".