1285557880381 has 2 divisors, whose sum is σ = 1285557880382. Its totient is φ = 1285557880380.

The previous prime is 1285557880361. The next prime is 1285557880429. The reversal of 1285557880381 is 1830887555821.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1278842077881 + 6715802500 = 1130859^2 + 81950^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1285557880381 is a prime.

It is a super-2 number, since 2×1285557880381² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1285557880301) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 642778940190 + 642778940191.

It is an arithmetic number, because the mean of its divisors is an integer number (642778940191).

Almost surely, 2^{1285557880381} is an apocalyptic number.

It is an amenable number.

1285557880381 is a deficient number, since it is larger than the sum of its proper divisors (1).

1285557880381 is an equidigital number, since it uses as much as digits as its factorization.

1285557880381 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 21504000, while the sum is 61.

The spelling of 1285557880381 in words is "one trillion, two hundred eighty-five billion, five hundred fifty-seven million, eight hundred eighty thousand, three hundred eighty-one".