1285885161 has 24 divisors (see below), whose sum is σ = 2081012544. Its totient is φ = 758259360.

The previous prime is 1285885141. The next prime is 1285885163. The reversal of 1285885161 is 1615885821.

1285885161 is a `hidden beast` number, since 1 + 2 + 8 + 588 + 5 + 1 + 61 = 666.

It is not a de Polignac number, because 1285885161 - 2²³ = 1277496553 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1285885163) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 171861 + ... + 179186.

It is an arithmetic number, because the mean of its divisors is an integer number (86708856).

Almost surely, 2^1285885161 is an apocalyptic number.

1285885161 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1285885161 is a deficient number, since it is larger than the sum of its proper divisors (795127383).

1285885161 is a wasteful number, since it uses less digits than its factorization.

1285885161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 351101 (or 351098 counting only the distinct ones).

The product of its digits is 153600, while the sum is 45.

The square root of 1285885161 is about 35859.2409428867. The cubic root of 1285885161 is about 1087.4285429069.

It can be divided in two parts, 1285 and 885161, that added together give a triangular number (886446 = T₁₃₃₁).

The spelling of 1285885161 in words is "one billion, two hundred eighty-five million, eight hundred eighty-five thousand, one hundred sixty-one".