6651240 has 64 divisors (see below), whose sum is σ = 20433600. Its totient is φ = 1731072.

The previous prime is 6651223. The next prime is 6651251. The reversal of 6651240 is 421566.

It is a Cunningham number, because it is equal to 2579²-1.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a self number, because there is not a number n which added to its sum of digits gives 6651240.

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 15 ways as a sum of consecutive naturals, for example, 4516 + ... + 5804.

It is an arithmetic number, because the mean of its divisors is an integer number (319275).

Almost surely, 2^6651240 is an apocalyptic number.

6651240 is a gapful number since it is divisible by the number (60) 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 6651240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (10216800).

6651240 is an abundant number, since it is smaller than the sum of its proper divisors (13782360).

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

6651240 is a wasteful number, since it uses less digits than its factorization.

6651240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1346 (or 1342 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 24.

The square root of 6651240 is about 2578.9998061264. Note that the first 3 decimals coincide. The cubic root of 6651240 is about 188.0619231658.

The spelling of 6651240 in words is "six million, six hundred fifty-one thousand, two hundred forty".