21762929 has 2 divisors, whose sum is σ = 21762930. Its totient is φ = 21762928.

The previous prime is 21762901. The next prime is 21762931. The reversal of 21762929 is 92926712.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20611600 + 1151329 = 4540^2 + 1073^2 .

It is a cyclic number.

It is not a de Polignac number, because 21762929 - 2¹² = 21758833 is a prime.

Together with 21762931, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 21762892 and 21762901.

It is not a weakly prime, because it can be changed into another prime (21762959) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a good prime.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10881464 + 10881465.

It is an arithmetic number, because the mean of its divisors is an integer number (10881465).

Almost surely, 2^21762929 is an apocalyptic number.

It is an amenable number.

21762929 is a deficient number, since it is larger than the sum of its proper divisors (1).

21762929 is an equidigital number, since it uses as much as digits as its factorization.

21762929 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 27216, while the sum is 38.

The square root of 21762929 is about 4665.0754549096. The cubic root of 21762929 is about 279.1938076926.

The spelling of 21762929 in words is "twenty-one million, seven hundred sixty-two thousand, nine hundred twenty-nine".