128666603520 has 832 divisors, whose sum is σ = 563205296640. Its totient is φ = 27136622592.

The previous prime is 128666603497. The next prime is 128666603531. The reversal of 128666603520 is 25306666821.

It is a tau number, because it is divible by the number of its divisors (832).

It is a super-2 number, since 2×128666603520² (a number of 23 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

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 63 ways as a sum of consecutive naturals, for example, 50318082 + ... + 50320638.

Almost surely, 2^128666603520 is an apocalyptic number.

128666603520 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 128666603520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (281602648320).

128666603520 is an abundant number, since it is smaller than the sum of its proper divisors (434538693120).

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

128666603520 is a wasteful number, since it uses less digits than its factorization.

128666603520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2615 (or 2587 counting only the distinct ones).

The product of its (nonzero) digits is 622080, while the sum is 45.

The spelling of 128666603520 in words is "one hundred twenty-eight billion, six hundred sixty-six million, six hundred three thousand, five hundred twenty".