21769453 has 2 divisors, whose sum is σ = 21769454. Its totient is φ = 21769452.

The previous prime is 21769417. The next prime is 21769487. The reversal of 21769453 is 35496712.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16670889 + 5098564 = 4083^2 + 2258^2 .

It is a cyclic number.

It is not a de Polignac number, because 21769453 - 2⁹ = 21768941 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21763453) 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, 10884726 + 10884727.

It is an arithmetic number, because the mean of its divisors is an integer number (10884727).

Almost surely, 2^21769453 is an apocalyptic number.

It is an amenable number.

21769453 is a deficient number, since it is larger than the sum of its proper divisors (1).

21769453 is an equidigital number, since it uses as much as digits as its factorization.

21769453 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 45360, while the sum is 37.

The square root of 21769453 is about 4665.7746409358. The cubic root of 21769453 is about 279.2217034234.

It can be divided in two parts, 21769 and 453, that added together give a palindrome (22222).

The spelling of 21769453 in words is "twenty-one million, seven hundred sixty-nine thousand, four hundred fifty-three".