128987420 has 24 divisors (see below), whose sum is σ = 271202064. Its totient is φ = 51532416.

The previous prime is 128987407. The next prime is 128987431. The reversal of 128987420 is 24789821.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15299 + ... + 22181.

It is an arithmetic number, because the mean of its divisors is an integer number (11300086).

Almost surely, 2^128987420 is an apocalyptic number.

128987420 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

128987420 is an abundant number, since it is smaller than the sum of its proper divisors (142214644).

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

128987420 is a wasteful number, since it uses less digits than its factorization.

128987420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7829 (or 7827 counting only the distinct ones).

The product of its (nonzero) digits is 64512, while the sum is 41.

The square root of 128987420 is about 11357.2628744782. The cubic root of 128987420 is about 505.2610094062.

The spelling of 128987420 in words is "one hundred twenty-eight million, nine hundred eighty-seven thousand, four hundred twenty".