21030329 has 2 divisors, whose sum is σ = 21030330. Its totient is φ = 21030328.

The previous prime is 21030313. The next prime is 21030337. The reversal of 21030329 is 92303012.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16386304 + 4644025 = 4048^2 + 2155^2 .

It is a cyclic number.

It is not a de Polignac number, because 21030329 - 2⁴ = 21030313 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a self number, because there is not a number n which added to its sum of digits gives 21030329.

It is not a weakly prime, because it can be changed into another prime (21030379) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10515164 + 10515165.

It is an arithmetic number, because the mean of its divisors is an integer number (10515165).

Almost surely, 2^21030329 is an apocalyptic number.

It is an amenable number.

21030329 is a deficient number, since it is larger than the sum of its proper divisors (1).

21030329 is an equidigital number, since it uses as much as digits as its factorization.

21030329 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 324, while the sum is 20.

The square root of 21030329 is about 4585.8836662087. The cubic root of 21030329 is about 276.0251718623.

The spelling of 21030329 in words is "twenty-one million, thirty thousand, three hundred twenty-nine".