256542156 has 72 divisors (see below), whose sum is σ = 700618464. Its totient is φ = 78681600.

The previous prime is 256542137. The next prime is 256542157. The reversal of 256542156 is 651245652.

256542156 is a `hidden beast` number, since 2 + 565 + 42 + 1 + 56 = 666.

256542156 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

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 256542156.

It is not an unprimeable number, because it can be changed into a prime (256542157) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 186985 + ... + 188351.

It is an arithmetic number, because the mean of its divisors is an integer number (9730812).

Almost surely, 2^256542156 is an apocalyptic number.

256542156 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 256542156, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (350309232).

256542156 is an abundant number, since it is smaller than the sum of its proper divisors (444076308).

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

256542156 is a wasteful number, since it uses less digits than its factorization.

256542156 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1791 (or 1786 counting only the distinct ones).

The product of its digits is 72000, while the sum is 36.

The square root of 256542156 is about 16016.9334143587. The cubic root of 256542156 is about 635.4083437976.

The spelling of 256542156 in words is "two hundred fifty-six million, five hundred forty-two thousand, one hundred fifty-six".