256401330 has 32 divisors (see below), whose sum is σ = 617721984. Its totient is φ = 68111616.

The previous prime is 256401317. The next prime is 256401337. The reversal of 256401330 is 33104652.

It is a happy number.

It is a super-3 number, since 3×256401330³ (a number of 26 digits) contains 333 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 256401330.

It is not an unprimeable number, because it can be changed into a prime (256401337) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 8359 + ... + 24138.

It is an arithmetic number, because the mean of its divisors is an integer number (19303812).

Almost surely, 2^256401330 is an apocalyptic number.

256401330 is an abundant number, since it is smaller than the sum of its proper divisors (361320654).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

256401330 is a wasteful number, since it uses less digits than its factorization.

256401330 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32770.

The product of its (nonzero) digits is 2160, while the sum is 24.

The square root of 256401330 is about 16012.5366510119. The cubic root of 256401330 is about 635.2920557052.

Adding to 256401330 its reverse (33104652), we get a palindrome (289505982).

The spelling of 256401330 in words is "two hundred fifty-six million, four hundred one thousand, three hundred thirty".