128699872 has 72 divisors (see below), whose sum is σ = 296903880. Its totient is φ = 54754560.

The previous prime is 128699833. The next prime is 128699887. The reversal of 128699872 is 278996821.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 330654 + ... + 331042.

It is an arithmetic number, because the mean of its divisors is an integer number (4123665).

Almost surely, 2^128699872 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 128699872, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (148451940).

128699872 is an abundant number, since it is smaller than the sum of its proper divisors (168204008).

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

128699872 is a wasteful number, since it uses less digits than its factorization.

128699872 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 624 (or 609 counting only the distinct ones).

The product of its digits is 870912, while the sum is 52.

The square root of 128699872 is about 11344.5965992626. The cubic root of 128699872 is about 504.8852753802.

The spelling of 128699872 in words is "one hundred twenty-eight million, six hundred ninety-nine thousand, eight hundred seventy-two".