13908421 has 2 divisors, whose sum is σ = 13908422. Its totient is φ = 13908420.

The previous prime is 13908409. The next prime is 13908439. The reversal of 13908421 is 12480931.

It is a happy number.

13908421 is digitally balanced in base 2, 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., 13771521 + 136900 = 3711^2 + 370^2 .

It is an emirp because it is prime and its reverse (12480931) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-13908421 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 13908421.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (13908451) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6954210 + 6954211.

It is an arithmetic number, because the mean of its divisors is an integer number (6954211).

Almost surely, 2^13908421 is an apocalyptic number.

It is an amenable number.

13908421 is a deficient number, since it is larger than the sum of its proper divisors (1).

13908421 is an equidigital number, since it uses as much as digits as its factorization.

13908421 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1728, while the sum is 28.

The square root of 13908421 is about 3729.3995495254. The cubic root of 13908421 is about 240.4875563198.

The spelling of 13908421 in words is "thirteen million, nine hundred eight thousand, four hundred twenty-one".