128302857 has 24 divisors (see below), whose sum is σ = 187816200. Its totient is φ = 84395520.

The previous prime is 128302849. The next prime is 128302871. The reversal of 128302857 is 758203821.

It can be written as a sum of positive squares in 4 ways, for example, as 18870336 + 109432521 = 4344^2 + 10461^2 .

It is not a de Polignac number, because 128302857 - 2³ = 128302849 is a prime.

It is a super-2 number, since 2×128302857² = 32923246228724898, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (128302847) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 322983 + ... + 323379.

It is an arithmetic number, because the mean of its divisors is an integer number (7825675).

Almost surely, 2^128302857 is an apocalyptic number.

It is an amenable number.

128302857 is a deficient number, since it is larger than the sum of its proper divisors (59513343).

128302857 is a wasteful number, since it uses less digits than its factorization.

128302857 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 793 (or 790 counting only the distinct ones).

The product of its (nonzero) digits is 26880, while the sum is 36.

The square root of 128302857 is about 11327.0851060633. The cubic root of 128302857 is about 504.3655817905.

The spelling of 128302857 in words is "one hundred twenty-eight million, three hundred two thousand, eight hundred fifty-seven".