13989421 has 2 divisors, whose sum is σ = 13989422. Its totient is φ = 13989420.

The previous prime is 13989407. The next prime is 13989427. The reversal of 13989421 is 12498931.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 13616100 + 373321 = 3690^2 + 611^2 .

It is an emirp because it is prime and its reverse (12498931) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 13989421 - 2⁵ = 13989389 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (13989427) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6994710 + 6994711.

It is an arithmetic number, because the mean of its divisors is an integer number (6994711).

Almost surely, 2^13989421 is an apocalyptic number.

It is an amenable number.

13989421 is a deficient number, since it is larger than the sum of its proper divisors (1).

13989421 is an equidigital number, since it uses as much as digits as its factorization.

13989421 is an evil number, because the sum of its binary digits is even.

The product of its digits is 15552, while the sum is 37.

The square root of 13989421 is about 3740.2434412749. The cubic root of 13989421 is about 240.9535042273.

The spelling of 13989421 in words is "thirteen million, nine hundred eighty-nine thousand, four hundred twenty-one".