21230969 has 2 divisors, whose sum is σ = 21230970. Its totient is φ = 21230968.

The previous prime is 21230959. The next prime is 21231029. The reversal of 21230969 is 96903212.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20611600 + 619369 = 4540^2 + 787^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21230969 is a prime.

It is a super-2 number, since 2×21230969² = 901508089357922, which contains 22 as substring.

It is a Chen prime.

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

It is not a weakly prime, because it can be changed into another prime (21230959) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10615484 + 10615485.

It is an arithmetic number, because the mean of its divisors is an integer number (10615485).

Almost surely, 2^21230969 is an apocalyptic number.

It is an amenable number.

21230969 is a deficient number, since it is larger than the sum of its proper divisors (1).

21230969 is an equidigital number, since it uses as much as digits as its factorization.

21230969 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5832, while the sum is 32.

The square root of 21230969 is about 4607.7075645054. The cubic root of 21230969 is about 276.9002016816.

The spelling of 21230969 in words is "twenty-one million, two hundred thirty thousand, nine hundred sixty-nine".