1987155144 has 96 divisors (see below), whose sum is σ = 5882560320. Its totient is φ = 602287488.

The previous prime is 1987155133. The next prime is 1987155151. The reversal of 1987155144 is 4415517891.

1987155144 is a `hidden beast` number, since 1 + 98 + 7 + 1 + 551 + 4 + 4 = 666.

It is a self number, because there is not a number n which added to its sum of digits gives 1987155144.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 46869 + ... + 78555.

It is an arithmetic number, because the mean of its divisors is an integer number (61276670).

Almost surely, 2^1987155144 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1987155144, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2941280160).

1987155144 is an abundant number, since it is smaller than the sum of its proper divisors (3895405176).

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

1987155144 is a wasteful number, since it uses less digits than its factorization.

1987155144 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31779 (or 31772 counting only the distinct ones).

The product of its digits is 201600, while the sum is 45.

The square root of 1987155144 is about 44577.5183696894. The cubic root of 1987155144 is about 1257.2180041610.

The spelling of 1987155144 in words is "one billion, nine hundred eighty-seven million, one hundred fifty-five thousand, one hundred forty-four".