21952573 has 2 divisors, whose sum is σ = 21952574. Its totient is φ = 21952572.

The previous prime is 21952571. The next prime is 21952577. The reversal of 21952573 is 37525912.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15077689 + 6874884 = 3883^2 + 2622^2 .

It is a cyclic number.

It is not a de Polignac number, because 21952573 - 2¹ = 21952571 is a prime.

It is a super-3 number, since 3×21952573³ (a number of 23 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

Together with 21952571, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21952571) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10976286 + 10976287.

It is an arithmetic number, because the mean of its divisors is an integer number (10976287).

Almost surely, 2^21952573 is an apocalyptic number.

It is an amenable number.

21952573 is a deficient number, since it is larger than the sum of its proper divisors (1).

21952573 is an equidigital number, since it uses as much as digits as its factorization.

21952573 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 18900, while the sum is 34.

The square root of 21952573 is about 4685.3572969412. The cubic root of 21952573 is about 280.0024362033.

The spelling of 21952573 in words is "twenty-one million, nine hundred fifty-two thousand, five hundred seventy-three".