13811645 has 4 divisors (see below), whose sum is σ = 16573980. Its totient is φ = 11049312.

The previous prime is 13811639. The next prime is 13811653. The reversal of 13811645 is 54611831.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 54611831 = 79 ⋅691289.

It can be written as a sum of positive squares in 2 ways, for example, as 6205081 + 7606564 = 2491^2 + 2758^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-13811645 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1381160 + ... + 1381169.

It is an arithmetic number, because the mean of its divisors is an integer number (4143495).

Almost surely, 2^13811645 is an apocalyptic number.

It is an amenable number.

13811645 is a deficient number, since it is larger than the sum of its proper divisors (2762335).

13811645 is an equidigital number, since it uses as much as digits as its factorization.

13811645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2762334.

The product of its digits is 2880, while the sum is 29.

The square root of 13811645 is about 3716.4021580017. The cubic root of 13811645 is about 239.9284798465.

The spelling of 13811645 in words is "thirteen million, eight hundred eleven thousand, six hundred forty-five".