21444953 has 2 divisors, whose sum is σ = 21444954. Its totient is φ = 21444952.

The previous prime is 21444931. The next prime is 21444961. The reversal of 21444953 is 35944412.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21418384 + 26569 = 4628^2 + 163^2 .

It is a cyclic number.

It is not a de Polignac number, because 21444953 - 2⁸ = 21444697 is a prime.

It is not a weakly prime, because it can be changed into another prime (21444923) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10722476 + 10722477.

It is an arithmetic number, because the mean of its divisors is an integer number (10722477).

Almost surely, 2^21444953 is an apocalyptic number.

It is an amenable number.

21444953 is a deficient number, since it is larger than the sum of its proper divisors (1).

21444953 is an equidigital number, since it uses as much as digits as its factorization.

21444953 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 17280, while the sum is 32.

The square root of 21444953 is about 4630.8695727692. The cubic root of 21444953 is about 277.8273732897.

The spelling of 21444953 in words is "twenty-one million, four hundred forty-four thousand, nine hundred fifty-three".