21454373 has 2 divisors, whose sum is σ = 21454374. Its totient is φ = 21454372.

The previous prime is 21454333. The next prime is 21454379. The reversal of 21454373 is 37345412.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16265089 + 5189284 = 4033^2 + 2278^2 .

It is a cyclic number.

It is not a de Polignac number, because 21454373 - 2¹⁶ = 21388837 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21454379) 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, 10727186 + 10727187.

It is an arithmetic number, because the mean of its divisors is an integer number (10727187).

Almost surely, 2^21454373 is an apocalyptic number.

It is an amenable number.

21454373 is a deficient number, since it is larger than the sum of its proper divisors (1).

21454373 is an equidigital number, since it uses as much as digits as its factorization.

21454373 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 10080, while the sum is 29.

The square root of 21454373 is about 4631.8865486970. The cubic root of 21454373 is about 277.8680472072.

Adding to 21454373 its reverse (37345412), we get a palindrome (58799785).

The spelling of 21454373 in words is "twenty-one million, four hundred fifty-four thousand, three hundred seventy-three".