1285985281 has 8 divisors (see below), whose sum is σ = 1556150400. Its totient is φ = 1037433408.

The previous prime is 1285985263. The next prime is 1285985321. The reversal of 1285985281 is 1825895821.

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 1285985281 - 2⁷ = 1285985153 is a prime.

It is a super-2 number, since 2×1285985281² = 3307516285897297922, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1285985231) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5403181 + ... + 5403418.

It is an arithmetic number, because the mean of its divisors is an integer number (194518800).

Almost surely, 2^1285985281 is an apocalyptic number.

It is an amenable number.

1285985281 is a deficient number, since it is larger than the sum of its proper divisors (270165119).

1285985281 is a wasteful number, since it uses less digits than its factorization.

1285985281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10806623.

The product of its digits is 460800, while the sum is 49.

The square root of 1285985281 is about 35860.6369296475. The cubic root of 1285985281 is about 1087.4567648465.

The spelling of 1285985281 in words is "one billion, two hundred eighty-five million, nine hundred eighty-five thousand, two hundred eighty-one".