1987654771647 has 12 divisors (see below), whose sum is σ = 2878632245320. Its totient is φ = 1321606864368.

The previous prime is 1987654771591. The next prime is 1987654771841. The reversal of 1987654771647 is 7461774567891.

1987654771647 is a `hidden beast` number, since 1 + 9 + 8 + 7 + 6 + 547 + 71 + 6 + 4 + 7 = 666.

It is not a de Polignac number, because 1987654771647 - 2⁷ = 1987654771519 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 (1987654971647) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 291356128 + ... + 291362949.

Almost surely, 2^{1987654771647} is an apocalyptic number.

1987654771647 is a deficient number, since it is larger than the sum of its proper divisors (890977473673).

1987654771647 is a wasteful number, since it uses less digits than its factorization.

1987654771647 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 582719462 (or 582719459 counting only the distinct ones).

The product of its digits is 497871360, while the sum is 72.

The spelling of 1987654771647 in words is "one trillion, nine hundred eighty-seven billion, six hundred fifty-four million, seven hundred seventy-one thousand, six hundred forty-seven".