1285001865 has 48 divisors (see below), whose sum is σ = 2695275648. Its totient is φ = 552872448.

The previous prime is 1285001857. The next prime is 1285001867. The reversal of 1285001865 is 5681005821.

It is not a de Polignac number, because 1285001865 - 2³ = 1285001857 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (1285001867) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 114627 + ... + 125336.

It is an arithmetic number, because the mean of its divisors is an integer number (56151576).

Almost surely, 2^1285001865 is an apocalyptic number.

1285001865 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1285001865 is an abundant number, since it is smaller than the sum of its proper divisors (1410273783).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1285001865 is a wasteful number, since it uses less digits than its factorization.

1285001865 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 239998 (or 239995 counting only the distinct ones).

The product of its (nonzero) digits is 19200, while the sum is 36.

The square root of 1285001865 is about 35846.9226712698. The cubic root of 1285001865 is about 1087.1794949286.

The spelling of 1285001865 in words is "one billion, two hundred eighty-five million, one thousand, eight hundred sixty-five".