128725222 has 4 divisors (see below), whose sum is σ = 193087836. Its totient is φ = 64362610.

The previous prime is 128725213. The next prime is 128725243. The reversal of 128725222 is 222527821.

It is a semiprime because it is the product of two primes.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32181304 + ... + 32181307.

It is an arithmetic number, because the mean of its divisors is an integer number (48271959).

Almost surely, 2^128725222 is an apocalyptic number.

128725222 is a deficient number, since it is larger than the sum of its proper divisors (64362614).

128725222 is an equidigital number, since it uses as much as digits as its factorization.

128725222 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 64362613.

The product of its digits is 8960, while the sum is 31.

The square root of 128725222 is about 11345.7138162392. The cubic root of 128725222 is about 504.9184222701.

The spelling of 128725222 in words is "one hundred twenty-eight million, seven hundred twenty-five thousand, two hundred twenty-two".