256816867345 has 8 divisors (see below), whose sum is σ = 308212237800. Its totient is φ = 205432162560.

The previous prime is 256816867339. The next prime is 256816867357. The reversal of 256816867345 is 543768618652.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 15543356929 + 241273510416 = 124673^2 + 491196^2 .

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

It is not a de Polignac number, because 256816867345 - 2⁷ = 256816867217 is a prime.

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, 2613346 + ... + 2709835.

It is an arithmetic number, because the mean of its divisors is an integer number (38526529725).

Almost surely, 2^256816867345 is an apocalyptic number.

It is an amenable number.

256816867345 is a deficient number, since it is larger than the sum of its proper divisors (51395370455).

256816867345 is an equidigital number, since it uses as much as digits as its factorization.

256816867345 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5332835.

The product of its digits is 58060800, while the sum is 61.

The spelling of 256816867345 in words is "two hundred fifty-six billion, eight hundred sixteen million, eight hundred sixty-seven thousand, three hundred forty-five".