128025021 has 8 divisors (see below), whose sum is σ = 179684320. Its totient is φ = 80857872.

The previous prime is 128025019. The next prime is 128025077. The reversal of 128025021 is 120520821.

It is a happy number.

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

It is not a de Polignac number, because 128025021 - 2¹ = 128025019 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 (128025091) 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, 1122970 + ... + 1123083.

It is an arithmetic number, because the mean of its divisors is an integer number (22460540).

Almost surely, 2^128025021 is an apocalyptic number.

It is an amenable number.

128025021 is a deficient number, since it is larger than the sum of its proper divisors (51659299).

128025021 is a wasteful number, since it uses less digits than its factorization.

128025021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2246075.

The product of its (nonzero) digits is 320, while the sum is 21.

The square root of 128025021 is about 11314.8142273747. The cubic root of 128025021 is about 504.0012558233.

Adding to 128025021 its reverse (120520821), we get a palindrome (248545842).

The spelling of 128025021 in words is "one hundred twenty-eight million, twenty-five thousand, twenty-one".