1031311009021 has 2 divisors, whose sum is σ = 1031311009022. Its totient is φ = 1031311009020.

The previous prime is 1031311009013. The next prime is 1031311009061. The reversal of 1031311009021 is 1209001131301.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 861900564996 + 169410444025 = 928386^2 + 411595^2 .

It is an emirp because it is prime and its reverse (1209001131301) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1031311009021 - 2³ = 1031311009013 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1031311008983 and 1031311009001.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1031311009061) 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, 515655504510 + 515655504511.

It is an arithmetic number, because the mean of its divisors is an integer number (515655504511).

Almost surely, 2^{1031311009021} is an apocalyptic number.

It is an amenable number.

1031311009021 is a deficient number, since it is larger than the sum of its proper divisors (1).

1031311009021 is an equidigital number, since it uses as much as digits as its factorization.

1031311009021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 162, while the sum is 22.

The spelling of 1031311009021 in words is "one trillion, thirty-one billion, three hundred eleven million, nine thousand, twenty-one".