1331022011981 has 2 divisors, whose sum is σ = 1331022011982. Its totient is φ = 1331022011980.

The previous prime is 1331022011929. The next prime is 1331022012029. The reversal of 1331022011981 is 1891102201331.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 936751043881 + 394270968100 = 967859^2 + 627910^2 .

It is a cyclic number.

It is not a de Polignac number, because 1331022011981 - 2¹⁰ = 1331022010957 is a prime.

It is a super-2 number, since 2×1331022011981² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1331022011281) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 665511005990 + 665511005991.

It is an arithmetic number, because the mean of its divisors is an integer number (665511005991).

Almost surely, 2^{1331022011981} is an apocalyptic number.

It is an amenable number.

1331022011981 is a deficient number, since it is larger than the sum of its proper divisors (1).

1331022011981 is an equidigital number, since it uses as much as digits as its factorization.

1331022011981 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 32.

The spelling of 1331022011981 in words is "one trillion, three hundred thirty-one billion, twenty-two million, eleven thousand, nine hundred eighty-one".