20405453 has 4 divisors (see below), whose sum is σ = 20710080. Its totient is φ = 20100828.

The previous prime is 20405443. The next prime is 20405459. The reversal of 20405453 is 35450402.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 20405453 - 2⁸ = 20405197 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20405459) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 152213 + ... + 152346.

It is an arithmetic number, because the mean of its divisors is an integer number (5177520).

Almost surely, 2^20405453 is an apocalyptic number.

It is an amenable number.

20405453 is a deficient number, since it is larger than the sum of its proper divisors (304627).

20405453 is an equidigital number, since it uses as much as digits as its factorization.

20405453 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 304626.

The product of its (nonzero) digits is 2400, while the sum is 23.

The square root of 20405453 is about 4517.2395331662. The cubic root of 20405453 is about 273.2637854319.

Adding to 20405453 its reverse (35450402), we get a palindrome (55855855).

The spelling of 20405453 in words is "twenty million, four hundred five thousand, four hundred fifty-three".