128211930 has 192 divisors, whose sum is σ = 434367360. Its totient is φ = 26611200.

The previous prime is 128211917. The next prime is 128211949. The reversal of 128211930 is 39112821.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a junction number, because it is equal to n+sod(n) for n = 128211894 and 128211903.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 145090 + ... + 145970.

It is an arithmetic number, because the mean of its divisors is an integer number (2262330).

Almost surely, 2^128211930 is an apocalyptic number.

128211930 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 128211930, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (217183680).

128211930 is an abundant number, since it is smaller than the sum of its proper divisors (306155430).

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

128211930 is a wasteful number, since it uses less digits than its factorization.

128211930 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 922 (or 909 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 27.

The square root of 128211930 is about 11323.0706965911. The cubic root of 128211930 is about 504.2464072888.

The spelling of 128211930 in words is "one hundred twenty-eight million, two hundred eleven thousand, nine hundred thirty".