285821752121 has 2 divisors, whose sum is σ = 285821752122. Its totient is φ = 285821752120.

The previous prime is 285821752087. The next prime is 285821752141. The reversal of 285821752121 is 121257128582.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 214706196496 + 71115555625 = 463364^2 + 266675^2 .

It is a cyclic number.

It is not a de Polignac number, because 285821752121 - 2³⁸ = 10943845177 is a prime.

It is a super-3 number, since 3×285821752121³ (a number of 35 digits) contains 333 as substring.

It is not a weakly prime, because it can be changed into another prime (285821752141) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 142910876060 + 142910876061.

It is an arithmetic number, because the mean of its divisors is an integer number (142910876061).

Almost surely, 2^285821752121 is an apocalyptic number.

It is an amenable number.

285821752121 is a deficient number, since it is larger than the sum of its proper divisors (1).

285821752121 is an equidigital number, since it uses as much as digits as its factorization.

285821752121 is an evil number, because the sum of its binary digits is even.

The product of its digits is 179200, while the sum is 44.

The spelling of 285821752121 in words is "two hundred eighty-five billion, eight hundred twenty-one million, seven hundred fifty-two thousand, one hundred twenty-one".