818641 has 4 divisors (see below), whose sum is σ = 846900. Its totient is φ = 790384.

The previous prime is 818621. The next prime is 818659. The reversal of 818641 is 146818.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 172225 + 646416 = 415^2 + 804^2 .

It is a cyclic number.

It is not a de Polignac number, because 818641 - 2¹¹ = 816593 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (818621) 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, 14086 + ... + 14143.

It is an arithmetic number, because the mean of its divisors is an integer number (211725).

2⁸¹⁸⁶⁴¹ is an apocalyptic number.

It is an amenable number.

818641 is a deficient number, since it is larger than the sum of its proper divisors (28259).

818641 is a wasteful number, since it uses less digits than its factorization.

818641 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28258.

The product of its digits is 1536, while the sum is 28.

The square root of 818641 is about 904.7878204308. The cubic root of 818641 is about 93.5472798905.

The spelling of 818641 in words is "eight hundred eighteen thousand, six hundred forty-one".