21011453 has 2 divisors, whose sum is σ = 21011454. Its totient is φ = 21011452.

The previous prime is 21011447. The next prime is 21011503. The reversal of 21011453 is 35411012.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19695844 + 1315609 = 4438^2 + 1147^2 .

It is a cyclic number.

It is not a de Polignac number, because 21011453 - 2¹⁴ = 20995069 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21011413) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10505726 + 10505727.

It is an arithmetic number, because the mean of its divisors is an integer number (10505727).

Almost surely, 2^21011453 is an apocalyptic number.

It is an amenable number.

21011453 is a deficient number, since it is larger than the sum of its proper divisors (1).

21011453 is an equidigital number, since it uses as much as digits as its factorization.

21011453 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 120, while the sum is 17.

The square root of 21011453 is about 4583.8251493703. The cubic root of 21011453 is about 275.9425640128.

Adding to 21011453 its reverse (35411012), we get a palindrome (56422465).

The spelling of 21011453 in words is "twenty-one million, eleven thousand, four hundred fifty-three".