803978866661 has 2 divisors, whose sum is σ = 803978866662. Its totient is φ = 803978866660.

The previous prime is 803978866637. The next prime is 803978866673. The reversal of 803978866661 is 166668879308.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 621046444225 + 182932422436 = 788065^2 + 427706^2 .

It is a cyclic number.

It is not a de Polignac number, because 803978866661 - 2¹⁴ = 803978850277 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 803978866591 and 803978866600.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (803978860661) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 401989433330 + 401989433331.

It is an arithmetic number, because the mean of its divisors is an integer number (401989433331).

Almost surely, 2^803978866661 is an apocalyptic number.

It is an amenable number.

803978866661 is a deficient number, since it is larger than the sum of its proper divisors (1).

803978866661 is an equidigital number, since it uses as much as digits as its factorization.

803978866661 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 125411328, while the sum is 68.

The spelling of 803978866661 in words is "eight hundred three billion, nine hundred seventy-eight million, eight hundred sixty-six thousand, six hundred sixty-one".