1987471728 has 120 divisors (see below), whose sum is σ = 6292680576. Its totient is φ = 602251200.

The previous prime is 1987471723. The next prime is 1987471729. The reversal of 1987471728 is 8271747891.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1987471723) 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 23 ways as a sum of consecutive naturals, for example, 19533 + ... + 66003.

Almost surely, 2^1987471728 is an apocalyptic number.

1987471728 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1987471728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3146340288).

1987471728 is an abundant number, since it is smaller than the sum of its proper divisors (4305208848).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1987471728 is a wasteful number, since it uses less digits than its factorization.

1987471728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 46505 (or 46487 counting only the distinct ones).

The product of its digits is 1580544, while the sum is 54.

The square root of 1987471728 is about 44581.0691661831. The cubic root of 1987471728 is about 1257.2847652577.

The spelling of 1987471728 in words is "one billion, nine hundred eighty-seven million, four hundred seventy-one thousand, seven hundred twenty-eight".