21599089 has 2 divisors, whose sum is σ = 21599090. Its totient is φ = 21599088.

The previous prime is 21599069. The next prime is 21599099. The reversal of 21599089 is 98099512.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15800625 + 5798464 = 3975^2 + 2408^2 .

It is a cyclic number.

It is not a de Polignac number, because 21599089 - 2¹¹ = 21597041 is a prime.

It is not a weakly prime, because it can be changed into another prime (21599059) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10799544 + 10799545.

It is an arithmetic number, because the mean of its divisors is an integer number (10799545).

Almost surely, 2^21599089 is an apocalyptic number.

It is an amenable number.

21599089 is a deficient number, since it is larger than the sum of its proper divisors (1).

21599089 is an equidigital number, since it uses as much as digits as its factorization.

21599089 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 58320, while the sum is 43.

The square root of 21599089 is about 4647.4820064203. The cubic root of 21599089 is about 278.4914146956.

The spelling of 21599089 in words is "twenty-one million, five hundred ninety-nine thousand, eighty-nine".