21143453 has 2 divisors, whose sum is σ = 21143454. Its totient is φ = 21143452.

The previous prime is 21143411. The next prime is 21143459. The reversal of 21143453 is 35434112.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21141604 + 1849 = 4598^2 + 43^2 .

It is a cyclic number.

It is not a de Polignac number, because 21143453 - 2⁸ = 21143197 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21143459) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10571726 + 10571727.

It is an arithmetic number, because the mean of its divisors is an integer number (10571727).

Almost surely, 2^21143453 is an apocalyptic number.

It is an amenable number.

21143453 is a deficient number, since it is larger than the sum of its proper divisors (1).

21143453 is an equidigital number, since it uses as much as digits as its factorization.

21143453 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1440, while the sum is 23.

The square root of 21143453 is about 4598.2010612847. The cubic root of 21143453 is about 276.5192083684.

Adding to 21143453 its reverse (35434112), we get a palindrome (56577565).

The spelling of 21143453 in words is "twenty-one million, one hundred forty-three thousand, four hundred fifty-three".