21735089 has 2 divisors, whose sum is σ = 21735090. Its totient is φ = 21735088.

The previous prime is 21735079. The next prime is 21735137. The reversal of 21735089 is 98053712.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21464689 + 270400 = 4633^2 + 520^2 .

It is a cyclic number.

It is not a de Polignac number, because 21735089 - 2⁴ = 21735073 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (21735029) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10867544 + 10867545.

It is an arithmetic number, because the mean of its divisors is an integer number (10867545).

Almost surely, 2^21735089 is an apocalyptic number.

It is an amenable number.

21735089 is a deficient number, since it is larger than the sum of its proper divisors (1).

21735089 is an equidigital number, since it uses as much as digits as its factorization.

21735089 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 15120, while the sum is 35.

The square root of 21735089 is about 4662.0906254598. The cubic root of 21735089 is about 279.0747049688.

The spelling of 21735089 in words is "twenty-one million, seven hundred thirty-five thousand, eighty-nine".