6991408 has 10 divisors (see below), whose sum is σ = 13545884. Its totient is φ = 3495696.

The previous prime is 6991381. The next prime is 6991417. The reversal of 6991408 is 8041996.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 218466 + ... + 218497.

Almost surely, 2^6991408 is an apocalyptic number.

It is an amenable number.

6991408 is a deficient number, since it is larger than the sum of its proper divisors (6554476).

6991408 is a wasteful number, since it uses less digits than its factorization.

6991408 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 436971 (or 436965 counting only the distinct ones).

The product of its (nonzero) digits is 15552, while the sum is 37.

The square root of 6991408 is about 2644.1270771277. The cubic root of 6991408 is about 191.2148200204.

The spelling of 6991408 in words is "six million, nine hundred ninety-one thousand, four hundred eight".