128294640 has 60 divisors (see below), whose sum is σ = 430858584. Its totient is φ = 34211712.

The previous prime is 128294633. The next prime is 128294641. The reversal of 128294640 is 46492821.

128294640 is a `hidden beast` number, since 1 + 2 + 8 + 2 + 9 + 4 + 640 = 666.

It is a tau number, because it is divible by the number of its divisors (60).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 128294595 and 128294604.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128294641) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 88374 + ... + 89813.

Almost surely, 2^128294640 is an apocalyptic number.

128294640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

128294640 is an abundant number, since it is smaller than the sum of its proper divisors (302563944).

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

128294640 is a wasteful number, since it uses less digits than its factorization.

128294640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 178206 (or 178197 counting only the distinct ones).

The product of its (nonzero) digits is 27648, while the sum is 36.

The square root of 128294640 is about 11326.7223855800. The cubic root of 128294640 is about 504.3548144011.

The spelling of 128294640 in words is "one hundred twenty-eight million, two hundred ninety-four thousand, six hundred forty".