1011978466661 has 2 divisors, whose sum is σ = 1011978466662. Its totient is φ = 1011978466660.

The previous prime is 1011978466601. The next prime is 1011978466663. The reversal of 1011978466661 is 1666648791101.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1011975640900 + 2825761 = 1005970^2 + 1681^2 .

It is a cyclic number.

It is not a de Polignac number, because 1011978466661 - 2¹⁰ = 1011978465637 is a prime.

It is a super-3 number, since 3×1011978466661³ (a number of 37 digits) contains 333 as substring.

Together with 1011978466663, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 1011978466597 and 1011978466606.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1011978466663) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 505989233330 + 505989233331.

It is an arithmetic number, because the mean of its divisors is an integer number (505989233331).

Almost surely, 2^{1011978466661} is an apocalyptic number.

It is an amenable number.

1011978466661 is a deficient number, since it is larger than the sum of its proper divisors (1).

1011978466661 is an equidigital number, since it uses as much as digits as its factorization.

1011978466661 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2612736, while the sum is 56.

The spelling of 1011978466661 in words is "one trillion, eleven billion, nine hundred seventy-eight million, four hundred sixty-six thousand, six hundred sixty-one".