256128007 has 4 divisors (see below), whose sum is σ = 256160016. Its totient is φ = 256096000.

The previous prime is 256127917. The next prime is 256128017. The reversal of 256128007 is 700821652.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 256128007 - 2²³ = 247739399 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 256128007.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256128017) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7998 + ... + 24004.

It is an arithmetic number, because the mean of its divisors is an integer number (64040004).

Almost surely, 2^256128007 is an apocalyptic number.

256128007 is a deficient number, since it is larger than the sum of its proper divisors (32009).

256128007 is a wasteful number, since it uses less digits than its factorization.

256128007 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32008.

The product of its (nonzero) digits is 6720, while the sum is 31.

The square root of 256128007 is about 16003.9997188203. Note that the first 3 decimals coincide. The cubic root of 256128007 is about 635.0662356767.

Adding to 256128007 its reverse (700821652), we get a palindrome (956949659).

The spelling of 256128007 in words is "two hundred fifty-six million, one hundred twenty-eight thousand, seven".