1285941887 has 4 divisors (see below), whose sum is σ = 1286545776. Its totient is φ = 1285338000.

The previous prime is 1285941871. The next prime is 1285941889. The reversal of 1285941887 is 7881495821.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1285941887 - 2⁴ = 1285941871 is a prime.

It is a super-2 number, since 2×1285941887² = 3307293073482241538, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1285941889) 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 in 3 ways as a sum of consecutive naturals, for example, 298739 + ... + 303012.

It is an arithmetic number, because the mean of its divisors is an integer number (321636444).

Almost surely, 2^1285941887 is an apocalyptic number.

1285941887 is a deficient number, since it is larger than the sum of its proper divisors (603889).

1285941887 is an equidigital number, since it uses as much as digits as its factorization.

1285941887 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 603888.

The product of its digits is 1290240, while the sum is 53.

The square root of 1285941887 is about 35860.0318878832. The cubic root of 1285941887 is about 1087.4445330762. Note that the first 3 decimals are identical.

The spelling of 1285941887 in words is "one billion, two hundred eighty-five million, nine hundred forty-one thousand, eight hundred eighty-seven".