13819661 has 4 divisors (see below), whose sum is σ = 13873692. Its totient is φ = 13765632.

The previous prime is 13819651. The next prime is 13819679. The reversal of 13819661 is 16691831.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 12145225 + 1674436 = 3485^2 + 1294^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-13819661 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 (13819651) 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, 26630 + ... + 27143.

It is an arithmetic number, because the mean of its divisors is an integer number (3468423).

Almost surely, 2^13819661 is an apocalyptic number.

It is an amenable number.

13819661 is a deficient number, since it is larger than the sum of its proper divisors (54031).

13819661 is an equidigital number, since it uses as much as digits as its factorization.

13819661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 54030.

The product of its digits is 7776, while the sum is 35.

The square root of 13819661 is about 3717.4804639702. The cubic root of 13819661 is about 239.9748874187.

The spelling of 13819661 in words is "thirteen million, eight hundred nineteen thousand, six hundred sixty-one".