806621 has 4 divisors (see below), whose sum is σ = 809952. Its totient is φ = 803292.

The previous prime is 806609. The next prime is 806639. The reversal of 806621 is 126608.

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 806621 - 2¹⁸ = 544477 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 (806671) 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, 1271 + ... + 1796.

It is an arithmetic number, because the mean of its divisors is an integer number (202488).

2⁸⁰⁶⁶²¹ is an apocalyptic number.

It is an amenable number.

806621 is a deficient number, since it is larger than the sum of its proper divisors (3331).

806621 is a wasteful number, since it uses less digits than its factorization.

806621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3330.

The product of its (nonzero) digits is 576, while the sum is 23.

The square root of 806621 is about 898.1208159262. The cubic root of 806621 is about 93.0871730519.

The spelling of 806621 in words is "eight hundred six thousand, six hundred twenty-one".