21835189 has 2 divisors, whose sum is σ = 21835190. Its totient is φ = 21835188.

The previous prime is 21835183. The next prime is 21835201. The reversal of 21835189 is 98153812.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 13032100 + 8803089 = 3610^2 + 2967^2 .

It is a cyclic number.

It is not a de Polignac number, because 21835189 - 2⁷ = 21835061 is a prime.

It is equal to p_1379458 and since 21835189 and 1379458 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21835183) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10917594 + 10917595.

It is an arithmetic number, because the mean of its divisors is an integer number (10917595).

Almost surely, 2^21835189 is an apocalyptic number.

It is an amenable number.

21835189 is a deficient number, since it is larger than the sum of its proper divisors (1).

21835189 is an equidigital number, since it uses as much as digits as its factorization.

21835189 is an evil number, because the sum of its binary digits is even.

The product of its digits is 17280, while the sum is 37.

The square root of 21835189 is about 4672.8138203870. The cubic root of 21835189 is about 279.5024710617.

The spelling of 21835189 in words is "twenty-one million, eight hundred thirty-five thousand, one hundred eighty-nine".