256147644 has 12 divisors (see below), whose sum is σ = 597677864. Its totient is φ = 85382544.

The previous prime is 256147643. The next prime is 256147651. The reversal of 256147644 is 446741652.

It is a tau number, because it is divible by the number of its divisors (12).

It is a super-2 number, since 2×256147644² = 131223231053501472, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256147643) 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, 10672807 + ... + 10672830.

Almost surely, 2^256147644 is an apocalyptic number.

It is an amenable number.

256147644 is an abundant number, since it is smaller than the sum of its proper divisors (341530220).

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

256147644 is a wasteful number, since it uses less digits than its factorization.

256147644 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21345644 (or 21345642 counting only the distinct ones).

The product of its digits is 161280, while the sum is 39.

The square root of 256147644 is about 16004.6132099467. The cubic root of 256147644 is about 635.0824651617.

It can be divided in two parts, 2561 and 47644, that added together give a palindrome (50205).

The spelling of 256147644 in words is "two hundred fifty-six million, one hundred forty-seven thousand, six hundred forty-four".