285661984901 has 2 divisors, whose sum is σ = 285661984902. Its totient is φ = 285661984900.

The previous prime is 285661984879. The next prime is 285661984961. The reversal of 285661984901 is 109489166582.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 270972302500 + 14689682401 = 520550^2 + 121201^2 .

It is a cyclic number.

It is not a de Polignac number, because 285661984901 - 2¹⁰ = 285661983877 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (285661984961) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 142830992450 + 142830992451.

It is an arithmetic number, because the mean of its divisors is an integer number (142830992451).

Almost surely, 2^285661984901 is an apocalyptic number.

It is an amenable number.

285661984901 is a deficient number, since it is larger than the sum of its proper divisors (1).

285661984901 is an equidigital number, since it uses as much as digits as its factorization.

285661984901 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 7464960, while the sum is 59.

The spelling of 285661984901 in words is "two hundred eighty-five billion, six hundred sixty-one million, nine hundred eighty-four thousand, nine hundred one".