3987851871 has 4 divisors (see below), whose sum is σ = 5317135832. Its totient is φ = 2658567912.

The previous prime is 3987851851. The next prime is 3987851893. The reversal of 3987851871 is 1781587893.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1781587893 = 3 ⋅593862631.

It is not a de Polignac number, because 3987851871 - 2¹⁰ = 3987850847 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3987851821) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 664641976 + ... + 664641981.

It is an arithmetic number, because the mean of its divisors is an integer number (1329283958).

Almost surely, 2^3987851871 is an apocalyptic number.

3987851871 is a deficient number, since it is larger than the sum of its proper divisors (1329283961).

3987851871 is a wasteful number, since it uses less digits than its factorization.

3987851871 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1329283960.

The product of its digits is 3386880, while the sum is 57.

The square root of 3987851871 is about 63149.4407813719. The cubic root of 3987851871 is about 1585.7924263220.

The spelling of 3987851871 in words is "three billion, nine hundred eighty-seven million, eight hundred fifty-one thousand, eight hundred seventy-one".