256620064 has 48 divisors (see below), whose sum is σ = 521240832. Its totient is φ = 124304128.

The previous prime is 256620053. The next prime is 256620073. The reversal of 256620064 is 460026652.

256620064 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 139857 + ... + 141679.

It is an arithmetic number, because the mean of its divisors is an integer number (10859184).

Almost surely, 2^256620064 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 256620064, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (260620416).

256620064 is an abundant number, since it is smaller than the sum of its proper divisors (264620768).

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

256620064 is a wasteful number, since it uses less digits than its factorization.

256620064 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1969 (or 1961 counting only the distinct ones).

The product of its (nonzero) digits is 17280, while the sum is 31.

The square root of 256620064 is about 16019.3652808093. The cubic root of 256620064 is about 635.4726586113.

The spelling of 256620064 in words is "two hundred fifty-six million, six hundred twenty thousand, sixty-four".