21800089 has 2 divisors, whose sum is σ = 21800090. Its totient is φ = 21800088.

The previous prime is 21800081. The next prime is 21800101. The reversal of 21800089 is 98000812.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16064064 + 5736025 = 4008^2 + 2395^2 .

It is a cyclic number.

It is not a de Polignac number, because 21800089 - 2³ = 21800081 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (21800081) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10900044 + 10900045.

It is an arithmetic number, because the mean of its divisors is an integer number (10900045).

Almost surely, 2^21800089 is an apocalyptic number.

It is an amenable number.

21800089 is a deficient number, since it is larger than the sum of its proper divisors (1).

21800089 is an equidigital number, since it uses as much as digits as its factorization.

21800089 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1152, while the sum is 28.

The square root of 21800089 is about 4669.0565428146. The cubic root of 21800089 is about 279.3526242825.

It can be divided in two parts, 218000 and 89, that added together give a square (218089 = 467²).

The spelling of 21800089 in words is "twenty-one million, eight hundred thousand, eighty-nine".