128772840 has 128 divisors (see below), whose sum is σ = 447068160. Its totient is φ = 29063424.

The previous prime is 128772827. The next prime is 128772851. The reversal of 128772840 is 48277821.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 68797 + ... + 70643.

It is an arithmetic number, because the mean of its divisors is an integer number (3492720).

Almost surely, 2^128772840 is an apocalyptic number.

128772840 is a gapful number since it is divisible by the number (10) 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 128772840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (223534080).

128772840 is an abundant number, since it is smaller than the sum of its proper divisors (318295320).

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

128772840 is a wasteful number, since it uses less digits than its factorization.

128772840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1951 (or 1947 counting only the distinct ones).

The product of its (nonzero) digits is 50176, while the sum is 39.

The square root of 128772840 is about 11347.8121239294. The cubic root of 128772840 is about 504.9806743577.

The spelling of 128772840 in words is "one hundred twenty-eight million, seven hundred seventy-two thousand, eight hundred forty".