1285706895521 has 2 divisors, whose sum is σ = 1285706895522. Its totient is φ = 1285706895520.

The previous prime is 1285706895427. The next prime is 1285706895527. The reversal of 1285706895521 is 1255986075821.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1171708827025 + 113998068496 = 1082455^2 + 337636^2 .

It is a cyclic number.

It is not a de Polignac number, because 1285706895521 - 2¹⁸ = 1285706633377 is a prime.

It is a super-2 number, since 2×1285706895521² (a number of 25 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1285706895527) 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, 642853447760 + 642853447761.

It is an arithmetic number, because the mean of its divisors is an integer number (642853447761).

Almost surely, 2^{1285706895521} is an apocalyptic number.

It is an amenable number.

1285706895521 is a deficient number, since it is larger than the sum of its proper divisors (1).

1285706895521 is an equidigital number, since it uses as much as digits as its factorization.

1285706895521 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 12096000, while the sum is 59.

The spelling of 1285706895521 in words is "one trillion, two hundred eighty-five billion, seven hundred six million, eight hundred ninety-five thousand, five hundred twenty-one".