1987128 has 96 divisors (see below), whose sum is σ = 6355440. Its totient is φ = 552960.

The previous prime is 1987127. The next prime is 1987151. The reversal of 1987128 is 8217891.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 1987092 and 1987101.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1987121) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 10200 + ... + 10392.

2^1987128 is an apocalyptic number.

1987128 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 1987128, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3177720).

1987128 is an abundant number, since it is smaller than the sum of its proper divisors (4368312).

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

1987128 is a wasteful number, since it uses less digits than its factorization.

1987128 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 229 (or 222 counting only the distinct ones).

The product of its digits is 8064, while the sum is 36.

The square root of 1987128 is about 1409.6552770092. The cubic root of 1987128 is about 125.7212279716.

It can be divided in two parts, 198 and 7128, that multiplied together give a square (1411344 = 1188²).

The spelling of 1987128 in words is "one million, nine hundred eighty-seven thousand, one hundred twenty-eight".