2491640 has 32 divisors (see below), whose sum is σ = 5654880. Its totient is φ = 988032.

The previous prime is 2491609. The next prime is 2491649. The reversal of 2491640 is 461942.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2491649) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6494 + ... + 6866.

It is an arithmetic number, because the mean of its divisors is an integer number (176715).

2^2491640 is an apocalyptic number.

2491640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2491640 is an abundant number, since it is smaller than the sum of its proper divisors (3163240).

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

2491640 is a wasteful number, since it uses less digits than its factorization.

2491640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 551 (or 547 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 26.

The square root of 2491640 is about 1578.4929521540. The cubic root of 2491640 is about 135.5694283432.

The spelling of 2491640 in words is "two million, four hundred ninety-one thousand, six hundred forty".