128221973 has 8 divisors (see below), whose sum is σ = 148106880. Its totient is φ = 109708480.

The previous prime is 128221967. The next prime is 128221993. The reversal of 128221973 is 379122821.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 128221973 - 2¹² = 128217877 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128221943) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 342653 + ... + 343026.

It is an arithmetic number, because the mean of its divisors is an integer number (18513360).

Almost surely, 2^128221973 is an apocalyptic number.

It is an amenable number.

128221973 is a deficient number, since it is larger than the sum of its proper divisors (19884907).

128221973 is a wasteful number, since it uses less digits than its factorization.

128221973 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 685707.

The product of its digits is 12096, while the sum is 35.

The square root of 128221973 is about 11323.5141630149. The cubic root of 128221973 is about 504.2595730279.

The spelling of 128221973 in words is "one hundred twenty-eight million, two hundred twenty-one thousand, nine hundred seventy-three".