256423151 has 4 divisors (see below), whose sum is σ = 259304400. Its totient is φ = 253541904.

The previous prime is 256423127. The next prime is 256423163. The reversal of 256423151 is 151324652.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-256423151 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256423171) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1440491 + ... + 1440668.

It is an arithmetic number, because the mean of its divisors is an integer number (64826100).

Almost surely, 2^256423151 is an apocalyptic number.

256423151 is a deficient number, since it is larger than the sum of its proper divisors (2881249).

256423151 is an equidigital number, since it uses as much as digits as its factorization.

256423151 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2881248.

The product of its digits is 7200, while the sum is 29.

The square root of 256423151 is about 16013.2180088825. The cubic root of 256423151 is about 635.3100773417.

The spelling of 256423151 in words is "two hundred fifty-six million, four hundred twenty-three thousand, one hundred fifty-one".