21200623 has 2 divisors, whose sum is σ = 21200624. Its totient is φ = 21200622.

The previous prime is 21200617. The next prime is 21200629. The reversal of 21200623 is 32600212.

It is a balanced prime because it is at equal distance from previous prime (21200617) and next prime (21200629).

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21200623 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21200597 and 21200606.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21200629) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10600311 + 10600312.

It is an arithmetic number, because the mean of its divisors is an integer number (10600312).

Almost surely, 2^21200623 is an apocalyptic number.

21200623 is a deficient number, since it is larger than the sum of its proper divisors (1).

21200623 is an equidigital number, since it uses as much as digits as its factorization.

21200623 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 144, while the sum is 16.

The square root of 21200623 is about 4604.4134262683. The cubic root of 21200623 is about 276.7682117858.

Adding to 21200623 its reverse (32600212), we get a palindrome (53800835).

The spelling of 21200623 in words is "twenty-one million, two hundred thousand, six hundred twenty-three".