128002257 has 18 divisors (see below), whose sum is σ = 186399798. Its totient is φ = 84644352.

The previous prime is 128002253. The next prime is 128002283. The reversal of 128002257 is 752200821.

It can be written as a sum of positive squares in 3 ways, for example, as 32764176 + 95238081 = 5724^2 + 9759^2 .

It is not a de Polignac number, because 128002257 - 2² = 128002253 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 128002257.

It is not an unprimeable number, because it can be changed into a prime (128002253) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 221553 + ... + 222129.

Almost surely, 2^128002257 is an apocalyptic number.

It is an amenable number.

128002257 is a deficient number, since it is larger than the sum of its proper divisors (58397541).

128002257 is an equidigital number, since it uses as much as digits as its factorization.

128002257 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 897 (or 737 counting only the distinct ones).

The product of its (nonzero) digits is 2240, while the sum is 27.

The square root of 128002257 is about 11313.8082447954. The cubic root of 128002257 is about 503.9713820674.

The spelling of 128002257 in words is "one hundred twenty-eight million, two thousand, two hundred fifty-seven".