321616231 has 4 divisors (see below), whose sum is σ = 322248600. Its totient is φ = 320983864.

The previous prime is 321616223. The next prime is 321616241. The reversal of 321616231 is 132616123.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 132616123 = 53 ⋅2502191.

It is a cyclic number.

It is not a de Polignac number, because 321616231 - 2³ = 321616223 is a prime.

It is a super-2 number, since 2×321616231² = 206874000085290722, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 321616196 and 321616205.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (321616201) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 315421 + ... + 316438.

It is an arithmetic number, because the mean of its divisors is an integer number (80562150).

Almost surely, 2^321616231 is an apocalyptic number.

321616231 is a deficient number, since it is larger than the sum of its proper divisors (632369).

321616231 is an equidigital number, since it uses as much as digits as its factorization.

321616231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 632368.

The product of its digits is 1296, while the sum is 25.

The square root of 321616231 is about 17933.6619517599. The cubic root of 321616231 is about 685.1399937648.

The spelling of 321616231 in words is "three hundred twenty-one million, six hundred sixteen thousand, two hundred thirty-one".