21233689 has 2 divisors, whose sum is σ = 21233690. Its totient is φ = 21233688.

The previous prime is 21233651. The next prime is 21233753. The reversal of 21233689 is 98633212.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21233664 + 25 = 4608^2 + 5^2 .

It is a cyclic number.

It is not a de Polignac number, because 21233689 - 2¹⁹ = 20709401 is a prime.

It is not a weakly prime, because it can be changed into another prime (21233609) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10616844 + 10616845.

It is an arithmetic number, because the mean of its divisors is an integer number (10616845).

Almost surely, 2^21233689 is an apocalyptic number.

It is an amenable number.

21233689 is a deficient number, since it is larger than the sum of its proper divisors (1).

21233689 is an equidigital number, since it uses as much as digits as its factorization.

21233689 is an evil number, because the sum of its binary digits is even.

The product of its digits is 15552, while the sum is 34.

The square root of 21233689 is about 4608.0027126728. The cubic root of 21233689 is about 276.9120261754.

The spelling of 21233689 in words is "twenty-one million, two hundred thirty-three thousand, six hundred eighty-nine".