6921408 has 112 divisors (see below), whose sum is σ = 20482560. Its totient is φ = 2049024.

The previous prime is 6921403. The next prime is 6921437. The reversal of 6921408 is 8041296.

It is not an unprimeable number, because it can be changed into a prime (6921403) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 117283 + ... + 117341.

It is an arithmetic number, because the mean of its divisors is an integer number (182880).

Almost surely, 2^6921408 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 6921408, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (10241280).

6921408 is an abundant number, since it is smaller than the sum of its proper divisors (13561152).

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

6921408 is a wasteful number, since it uses less digits than its factorization.

6921408 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 134 (or 124 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 30.

The square root of 6921408 is about 2630.8568946258. The cubic root of 6921408 is about 190.5745122228.

The spelling of 6921408 in words is "six million, nine hundred twenty-one thousand, four hundred eight".