21919753 has 2 divisors, whose sum is σ = 21919754. Its totient is φ = 21919752.

The previous prime is 21919741. The next prime is 21919757. The reversal of 21919753 is 35791912.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 13927824 + 7991929 = 3732^2 + 2827^2 .

It is a cyclic number.

It is not a de Polignac number, because 21919753 - 2¹⁷ = 21788681 is a prime.

It is not a weakly prime, because it can be changed into another prime (21919757) by changing a digit.

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

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10959876 + 10959877.

It is an arithmetic number, because the mean of its divisors is an integer number (10959877).

Almost surely, 2^21919753 is an apocalyptic number.

It is an amenable number.

21919753 is a deficient number, since it is larger than the sum of its proper divisors (1).

21919753 is an equidigital number, since it uses as much as digits as its factorization.

21919753 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 17010, while the sum is 37.

The square root of 21919753 is about 4681.8535859209. The cubic root of 21919753 is about 279.8628282188.

The spelling of 21919753 in words is "twenty-one million, nine hundred nineteen thousand, seven hundred fifty-three".