13724021 has 2 divisors, whose sum is σ = 13724022. Its totient is φ = 13724020.

The previous prime is 13724017. The next prime is 13724027. The reversal of 13724021 is 12042731.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 7623121 + 6100900 = 2761^2 + 2470^2 .

It is a cyclic number.

It is not a de Polignac number, because 13724021 - 2² = 13724017 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 13723984 and 13724002.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (13724027) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6862010 + 6862011.

It is an arithmetic number, because the mean of its divisors is an integer number (6862011).

Almost surely, 2^13724021 is an apocalyptic number.

It is an amenable number.

13724021 is a deficient number, since it is larger than the sum of its proper divisors (1).

13724021 is an equidigital number, since it uses as much as digits as its factorization.

13724021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 336, while the sum is 20.

The square root of 13724021 is about 3704.5945797077. The cubic root of 13724021 is about 239.4200173704.

Adding to 13724021 its reverse (12042731), we get a palindrome (25766752).

The spelling of 13724021 in words is "thirteen million, seven hundred twenty-four thousand, twenty-one".