321729927131 has 2 divisors, whose sum is σ = 321729927132. Its totient is φ = 321729927130.

The previous prime is 321729927091. The next prime is 321729927139. The reversal of 321729927131 is 131729927123.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-321729927131 is a prime.

It is a super-2 number, since 2×321729927131² (a number of 24 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (321729927139) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 160864963565 + 160864963566.

It is an arithmetic number, because the mean of its divisors is an integer number (160864963566).

Almost surely, 2^321729927131 is an apocalyptic number.

321729927131 is a deficient number, since it is larger than the sum of its proper divisors (1).

321729927131 is an equidigital number, since it uses as much as digits as its factorization.

321729927131 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 285768, while the sum is 47.

The spelling of 321729927131 in words is "three hundred twenty-one billion, seven hundred twenty-nine million, nine hundred twenty-seven thousand, one hundred thirty-one".