13436921 has 2 divisors, whose sum is σ = 13436922. Its totient is φ = 13436920.

The previous prime is 13436909. The next prime is 13436923. The reversal of 13436921 is 12963431.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12996025 + 440896 = 3605^2 + 664^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-13436921 is a prime.

Together with 13436923, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (13436923) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6718460 + 6718461.

It is an arithmetic number, because the mean of its divisors is an integer number (6718461).

Almost surely, 2^13436921 is an apocalyptic number.

It is an amenable number.

13436921 is a deficient number, since it is larger than the sum of its proper divisors (1).

13436921 is an equidigital number, since it uses as much as digits as its factorization.

13436921 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3888, while the sum is 29.

The square root of 13436921 is about 3665.6405988585. The cubic root of 13436921 is about 237.7387206369.

The spelling of 13436921 in words is "thirteen million, four hundred thirty-six thousand, nine hundred twenty-one".