128772120 has 64 divisors (see below), whose sum is σ = 406656000. Its totient is φ = 32531328.

The previous prime is 128772079. The next prime is 128772121. The reversal of 128772120 is 21277821.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128772121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 25960 + ... + 30519.

It is an arithmetic number, because the mean of its divisors is an integer number (6354000).

Almost surely, 2^128772120 is an apocalyptic number.

128772120 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

128772120 is an abundant number, since it is smaller than the sum of its proper divisors (277883880).

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

128772120 is a wasteful number, since it uses less digits than its factorization.

128772120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 56512 (or 56508 counting only the distinct ones).

The product of its (nonzero) digits is 3136, while the sum is 30.

The square root of 128772120 is about 11347.7803997081. The cubic root of 128772120 is about 504.9797331997.

The spelling of 128772120 in words is "one hundred twenty-eight million, seven hundred seventy-two thousand, one hundred twenty".