13765421 has 2 divisors, whose sum is σ = 13765422. Its totient is φ = 13765420.

The previous prime is 13765399. The next prime is 13765447. The reversal of 13765421 is 12456731.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11485321 + 2280100 = 3389^2 + 1510^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-13765421 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (13765471) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6882710 + 6882711.

It is an arithmetic number, because the mean of its divisors is an integer number (6882711).

Almost surely, 2^13765421 is an apocalyptic number.

It is an amenable number.

13765421 is a deficient number, since it is larger than the sum of its proper divisors (1).

13765421 is an equidigital number, since it uses as much as digits as its factorization.

13765421 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5040, while the sum is 29.

The square root of 13765421 is about 3710.1780280736. The cubic root of 13765421 is about 239.6605211927.

The spelling of 13765421 in words is "thirteen million, seven hundred sixty-five thousand, four hundred twenty-one".