256173126 has 64 divisors (see below), whose sum is σ = 599118336. Its totient is φ = 72230400.

The previous prime is 256173107. The next prime is 256173131. The reversal of 256173126 is 621371652.

It is a super-2 number, since 2×256173126² = 131249340969223752, which contains 22 as substring.

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

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 31 ways as a sum of consecutive naturals, for example, 53886 + ... + 58446.

It is an arithmetic number, because the mean of its divisors is an integer number (9361224).

Almost surely, 2^256173126 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 256173126, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (299559168).

256173126 is an abundant number, since it is smaller than the sum of its proper divisors (342945210).

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

256173126 is a wasteful number, since it uses less digits than its factorization.

256173126 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4637.

The product of its digits is 15120, while the sum is 33.

The square root of 256173126 is about 16005.4092731176. The cubic root of 256173126 is about 635.1035241553.

The spelling of 256173126 in words is "two hundred fifty-six million, one hundred seventy-three thousand, one hundred twenty-six".