2591640 has 96 divisors (see below), whose sum is σ = 8817120. Its totient is φ = 658944.

The previous prime is 2591623. The next prime is 2591669. The reversal of 2591640 is 461952.

2591640 = 139² + 140² + ... + 218².

2591640 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is an unprimeable number.

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 23 ways as a sum of consecutive naturals, for example, 8124 + ... + 8436.

It is an arithmetic number, because the mean of its divisors is an integer number (91845).

2^2591640 is an apocalyptic number.

2591640 is a gapful number since it is divisible by the number (20) 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 2591640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4408560).

2591640 is an abundant number, since it is smaller than the sum of its proper divisors (6225480).

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

2591640 is a wasteful number, since it uses less digits than its factorization.

2591640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 353 (or 346 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 27.

The square root of 2591640 is about 1609.8571365186. The cubic root of 2591640 is about 137.3593492884.

The spelling of 2591640 in words is "two million, five hundred ninety-one thousand, six hundred forty".