203131312381 has 2 divisors, whose sum is σ = 203131312382. Its totient is φ = 203131312380.

The previous prime is 203131312343. The next prime is 203131312403. The reversal of 203131312381 is 183213131302.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 112319489881 + 90811822500 = 335141^2 + 301350^2 .

It is a cyclic number.

It is not a de Polignac number, because 203131312381 - 2²⁷ = 202997094653 is a prime.

It is a super-2 number, since 2×203131312381² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (203131312081) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 101565656190 + 101565656191.

It is an arithmetic number, because the mean of its divisors is an integer number (101565656191).

Almost surely, 2^203131312381 is an apocalyptic number.

It is an amenable number.

203131312381 is a deficient number, since it is larger than the sum of its proper divisors (1).

203131312381 is an equidigital number, since it uses as much as digits as its factorization.

203131312381 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2592, while the sum is 28.

Adding to 203131312381 its reverse (183213131302), we get a palindrome (386344443683).

The spelling of 203131312381 in words is "two hundred three billion, one hundred thirty-one million, three hundred twelve thousand, three hundred eighty-one".