256535136 has 144 divisors (see below), whose sum is σ = 857198160. Its totient is φ = 71746560.

The previous prime is 256535107. The next prime is 256535177. The reversal of 256535136 is 631535652.

It is a tau number, because it is divible by the number of its divisors (144).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 256535136.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 38070 + ... + 44298.

It is an arithmetic number, because the mean of its divisors is an integer number (5952765).

Almost surely, 2^256535136 is an apocalyptic number.

256535136 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 256535136, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (428599080).

256535136 is an abundant number, since it is smaller than the sum of its proper divisors (600663024).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

256535136 is a wasteful number, since it uses less digits than its factorization.

256535136 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6269 (or 6258 counting only the distinct ones).

The product of its digits is 81000, while the sum is 36.

The square root of 256535136 is about 16016.7142697870. The cubic root of 256535136 is about 635.4025479896.

The spelling of 256535136 in words is "two hundred fifty-six million, five hundred thirty-five thousand, one hundred thirty-six".