2256138 has 48 divisors (see below), whose sum is σ = 5298696. Its totient is φ = 691200.

The previous prime is 2256131. The next prime is 2256169. The reversal of 2256138 is 8316522.

It can be written as a sum of positive squares in 4 ways, for example, as 2241009 + 15129 = 1497^2 + 123^2 .

It is not an unprimeable number, because it can be changed into a prime (2256131) 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, 22288 + ... + 22388.

2^2256138 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2256138, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2649348).

2256138 is an abundant number, since it is smaller than the sum of its proper divisors (3042558).

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

2256138 is a wasteful number, since it uses less digits than its factorization.

2256138 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 199 (or 196 counting only the distinct ones).

The product of its digits is 2880, while the sum is 27.

The square root of 2256138 is about 1502.0446065280. The cubic root of 2256138 is about 131.1561178969.

The spelling of 2256138 in words is "two million, two hundred fifty-six thousand, one hundred thirty-eight".