2581956 has 60 divisors (see below), whose sum is σ = 7280812. Its totient is φ = 793152.

The previous prime is 2581951. The next prime is 2581961. The reversal of 2581956 is 6591852.

It is a happy number.

2581956 is nontrivially palindromic in base 5.

2581956 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (2581951) and next prime (2581961).

It can be written as a sum of positive squares in 2 ways, for example, as 129600 + 2452356 = 360^2 + 1566^2 .

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 2581956.

It is not an unprimeable number, because it can be changed into a prime (2581951) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 3906 + ... + 4518.

2^2581956 is an apocalyptic number.

2581956 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 2581956, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3640406).

2581956 is an abundant number, since it is smaller than the sum of its proper divisors (4698856).

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

2581956 is a wasteful number, since it uses less digits than its factorization.

2581956 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 642 (or 631 counting only the distinct ones).

The product of its digits is 21600, while the sum is 36.

The square root of 2581956 is about 1606.8466012660. The cubic root of 2581956 is about 137.1880487228.

The spelling of 2581956 in words is "two million, five hundred eighty-one thousand, nine hundred fifty-six".