21536089 has 2 divisors, whose sum is σ = 21536090. Its totient is φ = 21536088.

The previous prime is 21536087. The next prime is 21536107. The reversal of 21536089 is 98063512.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20115225 + 1420864 = 4485^2 + 1192^2 .

It is a cyclic number.

It is not a de Polignac number, because 21536089 - 2¹ = 21536087 is a prime.

Together with 21536087, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (21536083) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10768044 + 10768045.

It is an arithmetic number, because the mean of its divisors is an integer number (10768045).

Almost surely, 2^21536089 is an apocalyptic number.

It is an amenable number.

21536089 is a deficient number, since it is larger than the sum of its proper divisors (1).

21536089 is an equidigital number, since it uses as much as digits as its factorization.

21536089 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 12960, while the sum is 34.

The square root of 21536089 is about 4640.6991930096. The cubic root of 21536089 is about 278.2203840495.

The spelling of 21536089 in words is "twenty-one million, five hundred thirty-six thousand, eighty-nine".