128377634661640 has 256 divisors, whose sum is σ = 366092015224320. Its totient is φ = 39431760076800.

The previous prime is 128377634661607. The next prime is 128377634661671. The reversal of 128377634661640 is 46166436773821.

It is a happy number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 21961540 + ... + 27185740.

It is an arithmetic number, because the mean of its divisors is an integer number (1430046934470).

Almost surely, 2^{128377634661640} is an apocalyptic number.

128377634661640 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 128377634661640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (183046007612160).

128377634661640 is an abundant number, since it is smaller than the sum of its proper divisors (237714380562680).

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

128377634661640 is a wasteful number, since it uses less digits than its factorization.

128377634661640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5224432 (or 5224428 counting only the distinct ones).

The product of its (nonzero) digits is 146313216, while the sum is 64.

The spelling of 128377634661640 in words is "one hundred twenty-eight trillion, three hundred seventy-seven billion, six hundred thirty-four million, six hundred sixty-one thousand, six hundred forty".