1987634709 has 48 divisors (see below), whose sum is σ = 3043735552. Its totient is φ = 1248234624.

The previous prime is 1987634699. The next prime is 1987634717. The reversal of 1987634709 is 9074367891.

It is a happy number.

It is not a de Polignac number, because 1987634709 - 2¹³ = 1987626517 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 (1987634009) by changing a digit.

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 47 ways as a sum of consecutive naturals, for example, 1817967 + ... + 1819059.

Almost surely, 2^1987634709 is an apocalyptic number.

It is an amenable number.

1987634709 is a deficient number, since it is larger than the sum of its proper divisors (1056100843).

1987634709 is a wasteful number, since it uses less digits than its factorization.

1987634709 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1306 (or 1303 counting only the distinct ones).

The product of its (nonzero) digits is 2286144, while the sum is 54.

The square root of 1987634709 is about 44582.8970458403. The cubic root of 1987634709 is about 1257.3191318559.

The spelling of 1987634709 in words is "one billion, nine hundred eighty-seven million, six hundred thirty-four thousand, seven hundred nine".