21422273 has 2 divisors, whose sum is σ = 21422274. Its totient is φ = 21422272.

The previous prime is 21422231. The next prime is 21422321. The reversal of 21422273 is 37222412.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20948929 + 473344 = 4577^2 + 688^2 .

It is a cyclic number.

It is not a de Polignac number, because 21422273 - 2¹⁰ = 21421249 is a prime.

It is not a weakly prime, because it can be changed into another prime (21422473) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10711136 + 10711137.

It is an arithmetic number, because the mean of its divisors is an integer number (10711137).

Almost surely, 2^21422273 is an apocalyptic number.

It is an amenable number.

21422273 is a deficient number, since it is larger than the sum of its proper divisors (1).

21422273 is an equidigital number, since it uses as much as digits as its factorization.

21422273 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1344, while the sum is 23.

The square root of 21422273 is about 4628.4201408256. The cubic root of 21422273 is about 277.7293961188.

Adding to 21422273 its reverse (37222412), we get a palindrome (58644685).

The spelling of 21422273 in words is "twenty-one million, four hundred twenty-two thousand, two hundred seventy-three".