128420667864 has 80 divisors (see below), whose sum is σ = 360343566000. Its totient is φ = 42729916608.

The previous prime is 128420667833. The next prime is 128420667887. The reversal of 128420667864 is 468766024821.

It is a happy number.

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

It is a self number, because there is not a number n which added to its sum of digits gives 128420667864.

It is a congruent 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 19 ways as a sum of consecutive naturals, for example, 183037 + ... + 538835.

It is an arithmetic number, because the mean of its divisors is an integer number (4504294575).

Almost surely, 2^128420667864 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 128420667864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (180171783000).

128420667864 is an abundant number, since it is smaller than the sum of its proper divisors (231922898136).

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

128420667864 is a wasteful number, since it uses less digits than its factorization.

128420667864 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 356374 (or 356361 counting only the distinct ones).

The product of its (nonzero) digits is 6193152, while the sum is 54.

The spelling of 128420667864 in words is "one hundred twenty-eight billion, four hundred twenty million, six hundred sixty-seven thousand, eight hundred sixty-four".