13766521 has 2 divisors, whose sum is σ = 13766522. Its totient is φ = 13766520.

The previous prime is 13766509. The next prime is 13766551. The reversal of 13766521 is 12566731.

13766521 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11634921 + 2131600 = 3411^2 + 1460^2 .

It is a cyclic number.

It is not a de Polignac number, because 13766521 - 2⁹ = 13766009 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (13766551) 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, 6883260 + 6883261.

It is an arithmetic number, because the mean of its divisors is an integer number (6883261).

Almost surely, 2^13766521 is an apocalyptic number.

It is an amenable number.

13766521 is a deficient number, since it is larger than the sum of its proper divisors (1).

13766521 is an equidigital number, since it uses as much as digits as its factorization.

13766521 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 7560, while the sum is 31.

The square root of 13766521 is about 3710.3262659772. The cubic root of 13766521 is about 239.6669048103. Note that the first 3 decimals are identical.

The spelling of 13766521 in words is "thirteen million, seven hundred sixty-six thousand, five hundred twenty-one".