1987316839 has 4 divisors (see below), whose sum is σ = 2029600224. Its totient is φ = 1945033456.

The previous prime is 1987316819. The next prime is 1987316861. The reversal of 1987316839 is 9386137891.

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

It is a cyclic number.

It is not a de Polignac number, because 1987316839 - 2²⁵ = 1953762407 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1987316839.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1987316819) 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, 21141622 + ... + 21141715.

It is an arithmetic number, because the mean of its divisors is an integer number (507400056).

Almost surely, 2^1987316839 is an apocalyptic number.

1987316839 is a deficient number, since it is larger than the sum of its proper divisors (42283385).

1987316839 is an equidigital number, since it uses as much as digits as its factorization.

1987316839 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42283384.

The product of its digits is 1959552, while the sum is 55.

The square root of 1987316839 is about 44579.3319712173. The cubic root of 1987316839 is about 1257.2521032184.

The spelling of 1987316839 in words is "one billion, nine hundred eighty-seven million, three hundred sixteen thousand, eight hundred thirty-nine".