128725440 has 56 divisors (see below), whose sum is σ = 408706320. Its totient is φ = 34326528.

The previous prime is 128725427. The next prime is 128725453. The reversal of 128725440 is 44527821.

It is an interprime number because it is at equal distance from previous prime (128725427) and next prime (128725453).

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, 66085 + ... + 68004.

Almost surely, 2^128725440 is an apocalyptic number.

128725440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

128725440 is an abundant number, since it is smaller than the sum of its proper divisors (279980880).

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

128725440 is a wasteful number, since it uses less digits than its factorization.

128725440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 134109 (or 134099 counting only the distinct ones).

The product of its (nonzero) digits is 17920, while the sum is 33.

The square root of 128725440 is about 11345.7234233873. The cubic root of 128725440 is about 504.9187073014.

The spelling of 128725440 in words is "one hundred twenty-eight million, seven hundred twenty-five thousand, four hundred forty".