13870421 has 2 divisors, whose sum is σ = 13870422. Its totient is φ = 13870420.

The previous prime is 13870391. The next prime is 13870427. The reversal of 13870421 is 12407831.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 11662225 + 2208196 = 3415^2 + 1486^2 .

It is an emirp because it is prime and its reverse (12407831) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 13870421 - 2¹⁰ = 13869397 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (13870427) 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, 6935210 + 6935211.

It is an arithmetic number, because the mean of its divisors is an integer number (6935211).

Almost surely, 2^13870421 is an apocalyptic number.

It is an amenable number.

13870421 is a deficient number, since it is larger than the sum of its proper divisors (1).

13870421 is an equidigital number, since it uses as much as digits as its factorization.

13870421 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1344, while the sum is 26.

The square root of 13870421 is about 3724.3014110031. The cubic root of 13870421 is about 240.2683399082.

The spelling of 13870421 in words is "thirteen million, eight hundred seventy thousand, four hundred twenty-one".