20897453 has 4 divisors (see below), whose sum is σ = 20930400. Its totient is φ = 20864508.

The previous prime is 20897431. The next prime is 20897477. The reversal of 20897453 is 35479802.

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 20897453 - 2²² = 16703149 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 (20897483) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15503 + ... + 16796.

It is an arithmetic number, because the mean of its divisors is an integer number (5232600).

Almost surely, 2^20897453 is an apocalyptic number.

It is an amenable number.

20897453 is a deficient number, since it is larger than the sum of its proper divisors (32947).

20897453 is an equidigital number, since it uses as much as digits as its factorization.

20897453 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32946.

The product of its (nonzero) digits is 60480, while the sum is 38.

The square root of 20897453 is about 4571.3732072540. The cubic root of 20897453 is about 275.4426062613.

The spelling of 20897453 in words is "twenty million, eight hundred ninety-seven thousand, four hundred fifty-three".