128049940 has 24 divisors (see below), whose sum is σ = 269694432. Its totient is φ = 51069600.

The previous prime is 128049937. The next prime is 128049953. The reversal of 128049940 is 49940821.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 128049940.

It is a congruent number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 2286 + ... + 16165.

It is an arithmetic number, because the mean of its divisors is an integer number (11237268).

Almost surely, 2^128049940 is an apocalyptic number.

128049940 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

128049940 is an abundant number, since it is smaller than the sum of its proper divisors (141644492).

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

128049940 is a wasteful number, since it uses less digits than its factorization.

128049940 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18807 (or 18805 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 37.

The square root of 128049940 is about 11315.9153407932. The cubic root of 128049940 is about 504.0339535789.

The spelling of 128049940 in words is "one hundred twenty-eight million, forty-nine thousand, nine hundred forty".