13781123 has 2 divisors, whose sum is σ = 13781124. Its totient is φ = 13781122.

The previous prime is 13781107. The next prime is 13781129. The reversal of 13781123 is 32118731.

It is a strong prime.

It is an emirp because it is prime and its reverse (32118731) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 13781123 - 2⁴ = 13781107 is a prime.

It is a super-2 number, since 2×13781123² = 379838702282258, which contains 22 as substring.

It is a Sophie Germain prime.

It is a junction number, because it is equal to n+sod(n) for n = 13781092 and 13781101.

It is not a weakly prime, because it can be changed into another prime (13781129) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6890561 + 6890562.

It is an arithmetic number, because the mean of its divisors is an integer number (6890562).

Almost surely, 2^13781123 is an apocalyptic number.

13781123 is a deficient number, since it is larger than the sum of its proper divisors (1).

13781123 is an equidigital number, since it uses as much as digits as its factorization.

13781123 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1008, while the sum is 26.

The square root of 13781123 is about 3712.2934959402. The cubic root of 13781123 is about 239.7516122330.

Adding to 13781123 its reverse (32118731), we get a palindrome (45899854).

The spelling of 13781123 in words is "thirteen million, seven hundred eighty-one thousand, one hundred twenty-three".