13621009 has 2 divisors, whose sum is σ = 13621010. Its totient is φ = 13621008.

The previous prime is 13621001. The next prime is 13621019. The reversal of 13621009 is 90012631.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 12816400 + 804609 = 3580^2 + 897^2 .

It is a cyclic number.

It is not a de Polignac number, because 13621009 - 2³ = 13621001 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (13621001) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6810504 + 6810505.

It is an arithmetic number, because the mean of its divisors is an integer number (6810505).

Almost surely, 2^13621009 is an apocalyptic number.

It is an amenable number.

13621009 is a deficient number, since it is larger than the sum of its proper divisors (1).

13621009 is an equidigital number, since it uses as much as digits as its factorization.

13621009 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 324, while the sum is 22.

The square root of 13621009 is about 3690.6651162087. The cubic root of 13621009 is about 238.8194863670.

The spelling of 13621009 in words is "thirteen million, six hundred twenty-one thousand, nine".