1967579869721 has 2 divisors, whose sum is σ = 1967579869722. Its totient is φ = 1967579869720.

The previous prime is 1967579869681. The next prime is 1967579869747. The reversal of 1967579869721 is 1279689757691.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1847250666496 + 120329203225 = 1359136^2 + 346885^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1967579869721 is a prime.

It is not a weakly prime, because it can be changed into another prime (1967579863721) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 983789934860 + 983789934861.

It is an arithmetic number, because the mean of its divisors is an integer number (983789934861).

Almost surely, 2^{1967579869721} is an apocalyptic number.

It is an amenable number.

1967579869721 is a deficient number, since it is larger than the sum of its proper divisors (1).

1967579869721 is an equidigital number, since it uses as much as digits as its factorization.

1967579869721 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 720135360, while the sum is 77.

The spelling of 1967579869721 in words is "one trillion, nine hundred sixty-seven billion, five hundred seventy-nine million, eight hundred sixty-nine thousand, seven hundred twenty-one".