256481511 has 16 divisors (see below), whose sum is σ = 401761920. Its totient is φ = 143485920.

The previous prime is 256481501. The next prime is 256481543. The reversal of 256481511 is 115184652.

It is not a de Polignac number, because 256481511 - 2¹³ = 256473319 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256481501) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 298501 + ... + 299358.

It is an arithmetic number, because the mean of its divisors is an integer number (25110120).

Almost surely, 2^256481511 is an apocalyptic number.

256481511 is a deficient number, since it is larger than the sum of its proper divisors (145280409).

256481511 is a wasteful number, since it uses less digits than its factorization.

256481511 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 597886.

The product of its digits is 9600, while the sum is 33.

The square root of 256481511 is about 16015.0401498092. The cubic root of 256481511 is about 635.3582709669.

The spelling of 256481511 in words is "two hundred fifty-six million, four hundred eighty-one thousand, five hundred eleven".