256643043 has 8 divisors (see below), whose sum is σ = 347800656. Its totient is φ = 168290400.

The previous prime is 256643029. The next prime is 256643047. The reversal of 256643043 is 340346652.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 256643043 - 2⁹ = 256642531 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 256642995 and 256643013.

It is not an unprimeable number, because it can be changed into a prime (256643047) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 701028 + ... + 701393.

It is an arithmetic number, because the mean of its divisors is an integer number (43475082).

Almost surely, 2^256643043 is an apocalyptic number.

256643043 is a deficient number, since it is larger than the sum of its proper divisors (91157613).

256643043 is a wasteful number, since it uses less digits than its factorization.

256643043 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1402485.

The product of its (nonzero) digits is 51840, while the sum is 33.

The square root of 256643043 is about 16020.0824904243. The cubic root of 256643043 is about 635.4916258089.

Adding to 256643043 its reverse (340346652), we get a palindrome (596989695).

The spelling of 256643043 in words is "two hundred fifty-six million, six hundred forty-three thousand, forty-three".