6643740 has 24 divisors (see below), whose sum is σ = 18602640. Its totient is φ = 1771648.

The previous prime is 6643739. The next prime is 6643781. The reversal of 6643740 is 473466.

It is a hoax number, since the sum of its digits (30) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 6643698 and 6643707.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 55305 + ... + 55424.

It is an arithmetic number, because the mean of its divisors is an integer number (775110).

Almost surely, 2^6643740 is an apocalyptic number.

6643740 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

6643740 is an abundant number, since it is smaller than the sum of its proper divisors (11958900).

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

6643740 is a wasteful number, since it uses less digits than its factorization.

6643740 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 110741 (or 110739 counting only the distinct ones).

The product of its (nonzero) digits is 12096, while the sum is 30.

The square root of 6643740 is about 2577.5453439270. The cubic root of 6643740 is about 187.9912097897.

The spelling of 6643740 in words is "six million, six hundred forty-three thousand, seven hundred forty".