13628821 has 2 divisors, whose sum is σ = 13628822. Its totient is φ = 13628820.

The previous prime is 13628819. The next prime is 13628827. The reversal of 13628821 is 12882631.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 10150596 + 3478225 = 3186^2 + 1865^2 .

It is an emirp because it is prime and its reverse (12882631) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 13628821 - 2¹ = 13628819 is a prime.

Together with 13628819, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (13628827) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6814410 + 6814411.

It is an arithmetic number, because the mean of its divisors is an integer number (6814411).

Almost surely, 2^13628821 is an apocalyptic number.

It is an amenable number.

13628821 is a deficient number, since it is larger than the sum of its proper divisors (1).

13628821 is an equidigital number, since it uses as much as digits as its factorization.

13628821 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4608, while the sum is 31.

The square root of 13628821 is about 3691.7233103254. The cubic root of 13628821 is about 238.8651340199.

The spelling of 13628821 in words is "thirteen million, six hundred twenty-eight thousand, eight hundred twenty-one".