321812861 has 16 divisors (see below), whose sum is σ = 343203840. Its totient is φ = 300898800.

The previous prime is 321812857. The next prime is 321812867. The reversal of 321812861 is 168218123.

It is a cyclic number.

It is not a de Polignac number, because 321812861 - 2² = 321812857 is a prime.

It is a Smith number, since the sum of its digits (32) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (321812867) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 639536 + ... + 640038.

It is an arithmetic number, because the mean of its divisors is an integer number (21450240).

Almost surely, 2^321812861 is an apocalyptic number.

It is an amenable number.

321812861 is a deficient number, since it is larger than the sum of its proper divisors (21390979).

321812861 is a wasteful number, since it uses less digits than its factorization.

321812861 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 896.

The product of its digits is 4608, while the sum is 32.

The square root of 321812861 is about 17939.1432627091. The cubic root of 321812861 is about 685.2795924733.

The spelling of 321812861 in words is "three hundred twenty-one million, eight hundred twelve thousand, eight hundred sixty-one".