320319981 has 8 divisors (see below), whose sum is σ = 474548160. Its totient is φ = 213546636.

The previous prime is 320319973. The next prime is 320320037. The reversal of 320319981 is 189913023.

It is not a de Polignac number, because 320319981 - 2³ = 320319973 is a prime.

It is a super-2 number, since 2×320319981² = 205209780455680722, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (320319481) 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 7 ways as a sum of consecutive naturals, for example, 5931825 + ... + 5931878.

It is an arithmetic number, because the mean of its divisors is an integer number (59318520).

Almost surely, 2^320319981 is an apocalyptic number.

It is an amenable number.

320319981 is a deficient number, since it is larger than the sum of its proper divisors (154228179).

320319981 is a wasteful number, since it uses less digits than its factorization.

320319981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11863712 (or 11863706 counting only the distinct ones).

The product of its (nonzero) digits is 11664, while the sum is 36.

The square root of 320319981 is about 17897.4853261569. The cubic root of 320319981 is about 684.2182859785.

The spelling of 320319981 in words is "three hundred twenty million, three hundred nineteen thousand, nine hundred eighty-one".