1871256985 has 16 divisors (see below), whose sum is σ = 2425006080. Its totient is φ = 1377984960.

The previous prime is 1871256941. The next prime is 1871256991. The reversal of 1871256985 is 5896521781.

It is not a de Polignac number, because 1871256985 - 2²³ = 1862868377 is a prime.

It is a super-2 number, since 2×1871256985² = 7003205407822580450, which contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 16761 + ... + 63430.

It is an arithmetic number, because the mean of its divisors is an integer number (151562880).

Almost surely, 2^1871256985 is an apocalyptic number.

It is an amenable number.

1871256985 is a deficient number, since it is larger than the sum of its proper divisors (553749095).

1871256985 is a wasteful number, since it uses less digits than its factorization.

1871256985 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 80568.

The product of its digits is 1209600, while the sum is 52.

The square root of 1871256985 is about 43258.0279832542. The cubic root of 1871256985 is about 1232.2849511037.

The spelling of 1871256985 in words is "one billion, eight hundred seventy-one million, two hundred fifty-six thousand, nine hundred eighty-five".