128987760 has 80 divisors (see below), whose sum is σ = 436222080. Its totient is φ = 31269120.

The previous prime is 128987741. The next prime is 128987777. The reversal of 128987760 is 67789821.

It is a tau number, because it is divible by the number of its divisors (80).

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 21790 + ... + 27069.

It is an arithmetic number, because the mean of its divisors is an integer number (5452776).

Almost surely, 2^128987760 is an apocalyptic number.

128987760 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

128987760 is an abundant number, since it is smaller than the sum of its proper divisors (307234320).

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

128987760 is a wasteful number, since it uses less digits than its factorization.

128987760 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 48886 (or 48880 counting only the distinct ones).

The product of its (nonzero) digits is 338688, while the sum is 48.

The square root of 128987760 is about 11357.2778428636. The cubic root of 128987760 is about 505.2614533477.

The spelling of 128987760 in words is "one hundred twenty-eight million, nine hundred eighty-seven thousand, seven hundred sixty".