1285161171821 has 8 divisors (see below), whose sum is σ = 1296302703264. Its totient is φ = 1274059361520.

The previous prime is 1285161171817. The next prime is 1285161171839. The reversal of 1285161171821 is 1281711615821.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1285161171821 - 2² = 1285161171817 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1285161171121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9865295 + ... + 9994716.

It is an arithmetic number, because the mean of its divisors is an integer number (162037837908).

Almost surely, 2^{1285161171821} is an apocalyptic number.

It is an amenable number.

1285161171821 is a deficient number, since it is larger than the sum of its proper divisors (11141531443).

1285161171821 is a wasteful number, since it uses less digits than its factorization.

1285161171821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19860571.

The product of its digits is 53760, while the sum is 44.

The spelling of 1285161171821 in words is "one trillion, two hundred eighty-five billion, one hundred sixty-one million, one hundred seventy-one thousand, eight hundred twenty-one".