21002329 has 2 divisors, whose sum is σ = 21002330. Its totient is φ = 21002328.

The previous prime is 21002323. The next prime is 21002341. The reversal of 21002329 is 92320012.

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., 20912329 + 90000 = 4573^2 + 300^2 .

It is a cyclic number.

It is not a de Polignac number, because 21002329 - 2¹³ = 20994137 is a prime.

It is not a weakly prime, because it can be changed into another prime (21002323) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10501164 + 10501165.

It is an arithmetic number, because the mean of its divisors is an integer number (10501165).

Almost surely, 2^21002329 is an apocalyptic number.

It is an amenable number.

21002329 is a deficient number, since it is larger than the sum of its proper divisors (1).

21002329 is an equidigital number, since it uses as much as digits as its factorization.

21002329 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 216, while the sum is 19.

The square root of 21002329 is about 4582.8298026438. The cubic root of 21002329 is about 275.9026165220.

The spelling of 21002329 in words is "twenty-one million, two thousand, three hundred twenty-nine".