128782640138040 has 1024 divisors, whose sum is σ = 507665055744000. Its totient is φ = 28433029847040.

The previous prime is 128782640137997. The next prime is 128782640138069. The reversal of 128782640138040 is 40831046287821.

128782640138040 is a `hidden beast` number, since 1 + 2 + 87 + 82 + 6 + 401 + 3 + 80 + 4 + 0 = 666.

It is a super-2 number, since 2×128782640138040² (a number of 29 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 255 ways as a sum of consecutive naturals, for example, 6666103501 + ... + 6666122819.

It is an arithmetic number, because the mean of its divisors is an integer number (495766656000).

Almost surely, 2^{128782640138040} is an apocalyptic number.

128782640138040 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 128782640138040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (253832527872000).

128782640138040 is an abundant number, since it is smaller than the sum of its proper divisors (378882415605960).

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

128782640138040 is a wasteful number, since it uses less digits than its factorization.

128782640138040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19657 (or 19647 counting only the distinct ones).

The product of its (nonzero) digits is 4128768, while the sum is 54.

The spelling of 128782640138040 in words is "one hundred twenty-eight trillion, seven hundred eighty-two billion, six hundred forty million, one hundred thirty-eight thousand, forty".