1987457071 has 4 divisors (see below), whose sum is σ = 2073868272. Its totient is φ = 1901045872.

The previous prime is 1987457051. The next prime is 1987457099. The reversal of 1987457071 is 1707547891.

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 1987457071 - 2¹⁵ = 1987424303 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 (1987457051) 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 3 ways as a sum of consecutive naturals, for example, 43205566 + ... + 43205611.

It is an arithmetic number, because the mean of its divisors is an integer number (518467068).

Almost surely, 2^1987457071 is an apocalyptic number.

1987457071 is a deficient number, since it is larger than the sum of its proper divisors (86411201).

1987457071 is an equidigital number, since it uses as much as digits as its factorization.

1987457071 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 86411200.

The product of its (nonzero) digits is 493920, while the sum is 49.

The square root of 1987457071 is about 44580.9047799616. The cubic root of 1987457071 is about 1257.2816745524.

The spelling of 1987457071 in words is "one billion, nine hundred eighty-seven million, four hundred fifty-seven thousand, seventy-one".