818472321 has 6 divisors (see below), whose sum is σ = 1182237810. Its totient is φ = 545648208.

The previous prime is 818472313. The next prime is 818472331. The reversal of 818472321 is 123274818.

It can be written as a sum of positive squares in only one way, i.e., 809687025 + 8785296 = 28455^2 + 2964^2 .

It is not a de Polignac number, because 818472321 - 2³ = 818472313 is a prime.

It is not an unprimeable number, because it can be changed into a prime (818472331) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 45470676 + ... + 45470693.

It is an arithmetic number, because the mean of its divisors is an integer number (197039635).

Almost surely, 2^818472321 is an apocalyptic number.

It is an amenable number.

818472321 is a deficient number, since it is larger than the sum of its proper divisors (363765489).

818472321 is a wasteful number, since it uses less digits than its factorization.

818472321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 90941375 (or 90941372 counting only the distinct ones).

The product of its digits is 21504, while the sum is 36.

The square root of 818472321 is about 28608.9552587996. The cubic root of 818472321 is about 935.4085438549.

The spelling of 818472321 in words is "eight hundred eighteen million, four hundred seventy-two thousand, three hundred twenty-one".