256380166849 has 4 divisors (see below), whose sum is σ = 261835064064. Its totient is φ = 250925269636.

The previous prime is 256380166807. The next prime is 256380166873. The reversal of 256380166849 is 948661083652.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 256380166849 - 2²⁷ = 256245949121 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 256380166793 and 256380166802.

It is not an unprimeable number, because it can be changed into a prime (256380166249) 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, 2727448537 + ... + 2727448630.

It is an arithmetic number, because the mean of its divisors is an integer number (65458766016).

Almost surely, 2^256380166849 is an apocalyptic number.

It is an amenable number.

256380166849 is a deficient number, since it is larger than the sum of its proper divisors (5454897215).

256380166849 is an equidigital number, since it uses as much as digits as its factorization.

256380166849 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5454897214.

The product of its (nonzero) digits is 14929920, while the sum is 58.

The spelling of 256380166849 in words is "two hundred fifty-six billion, three hundred eighty million, one hundred sixty-six thousand, eight hundred forty-nine".