21136589 has 2 divisors, whose sum is σ = 21136590. Its totient is φ = 21136588.

The previous prime is 21136579. The next prime is 21136601. The reversal of 21136589 is 98563112.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 14760964 + 6375625 = 3842^2 + 2525^2 .

It is a cyclic number.

It is not a de Polignac number, because 21136589 - 2¹² = 21132493 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21136519) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10568294 + 10568295.

It is an arithmetic number, because the mean of its divisors is an integer number (10568295).

Almost surely, 2^21136589 is an apocalyptic number.

It is an amenable number.

21136589 is a deficient number, since it is larger than the sum of its proper divisors (1).

21136589 is an equidigital number, since it uses as much as digits as its factorization.

21136589 is an evil number, because the sum of its binary digits is even.

The product of its digits is 12960, while the sum is 35.

The square root of 21136589 is about 4597.4546218533. The cubic root of 21136589 is about 276.4892821106.

The spelling of 21136589 in words is "twenty-one million, one hundred thirty-six thousand, five hundred eighty-nine".