231000321997 has 2 divisors, whose sum is σ = 231000321998. Its totient is φ = 231000321996.

The previous prime is 231000321989. The next prime is 231000322037. The reversal of 231000321997 is 799123000132.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 205486329636 + 25513992361 = 453306^2 + 159731^2 .

It is a cyclic number.

It is not a de Polignac number, because 231000321997 - 2³ = 231000321989 is a prime.

It is a super-2 number, since 2×231000321997² (a number of 24 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (231040321997) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 115500160998 + 115500160999.

It is an arithmetic number, because the mean of its divisors is an integer number (115500160999).

Almost surely, 2^231000321997 is an apocalyptic number.

It is an amenable number.

231000321997 is a deficient number, since it is larger than the sum of its proper divisors (1).

231000321997 is an equidigital number, since it uses as much as digits as its factorization.

231000321997 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 20412, while the sum is 37.

The spelling of 231000321997 in words is "two hundred thirty-one billion, three hundred twenty-one thousand, nine hundred ninety-seven".