3931775988487 has 4 divisors (see below), whose sum is σ = 3931907678800. Its totient is φ = 3931644298176.

The previous prime is 3931775988473. The next prime is 3931775988521. The reversal of 3931775988487 is 7848895771393.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-3931775988487 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 (3931775988457) 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, 65800362 + ... + 65860087.

It is an arithmetic number, because the mean of its divisors is an integer number (982976919700).

Almost surely, 2^{3931775988487} is an apocalyptic number.

3931775988487 is a deficient number, since it is larger than the sum of its proper divisors (131690313).

3931775988487 is a wasteful number, since it uses less digits than its factorization.

3931775988487 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 131690312.

The product of its digits is 2560481280, while the sum is 79.

The spelling of 3931775988487 in words is "three trillion, nine hundred thirty-one billion, seven hundred seventy-five million, nine hundred eighty-eight thousand, four hundred eighty-seven".