13781197 has 4 divisors (see below), whose sum is σ = 13907740. Its totient is φ = 13654656.

The previous prime is 13781179. The next prime is 13781221. The reversal of 13781197 is 79118731.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 79118731 = 17 ⋅4654043.

It can be written as a sum of positive squares in 2 ways, for example, as 10634121 + 3147076 = 3261^2 + 1774^2 .

It is a cyclic number.

It is not a de Polignac number, because 13781197 - 2¹¹ = 13779149 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 (13781107) 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, 63108 + ... + 63325.

It is an arithmetic number, because the mean of its divisors is an integer number (3476935).

Almost surely, 2^13781197 is an apocalyptic number.

It is an amenable number.

13781197 is a deficient number, since it is larger than the sum of its proper divisors (126543).

13781197 is a wasteful number, since it uses less digits than its factorization.

13781197 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 126542.

The product of its digits is 10584, while the sum is 37.

The square root of 13781197 is about 3712.3034628112. The cubic root of 13781197 is about 239.7520413607.

The spelling of 13781197 in words is "thirteen million, seven hundred eighty-one thousand, one hundred ninety-seven".