821453 has 4 divisors (see below), whose sum is σ = 823680. Its totient is φ = 819228.

The previous prime is 821449. The next prime is 821459. The reversal of 821453 is 354128.

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 821453 - 2² = 821449 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 (821459) 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, 413 + ... + 1346.

It is an arithmetic number, because the mean of its divisors is an integer number (205920).

2⁸²¹⁴⁵³ is an apocalyptic number.

It is an amenable number.

821453 is a deficient number, since it is larger than the sum of its proper divisors (2227).

821453 is a wasteful number, since it uses less digits than its factorization.

821453 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2226.

The product of its digits is 960, while the sum is 23.

The square root of 821453 is about 906.3404437627. The cubic root of 821453 is about 93.6542679068.

The spelling of 821453 in words is "eight hundred twenty-one thousand, four hundred fifty-three".