6991740 has 144 divisors (see below), whose sum is σ = 25159680. Its totient is φ = 1537920.

The previous prime is 6991729. The next prime is 6991741. The reversal of 6991740 is 471996.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 6991695 and 6991704.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6991741) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 38971 + ... + 39149.

It is an arithmetic number, because the mean of its divisors is an integer number (174720).

Almost surely, 2^6991740 is an apocalyptic number.

6991740 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 6991740, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (12579840).

6991740 is an abundant number, since it is smaller than the sum of its proper divisors (18167940).

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

6991740 is a wasteful number, since it uses less digits than its factorization.

6991740 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 232 (or 227 counting only the distinct ones).

The product of its (nonzero) digits is 13608, while the sum is 36.

The square root of 6991740 is about 2644.1898570262. The cubic root of 6991740 is about 191.2178467028.

It can be divided in two parts, 69 and 91740, that added together give a square (91809 = 303²).

The spelling of 6991740 in words is "six million, nine hundred ninety-one thousand, seven hundred forty".