6991478 has 16 divisors (see below), whose sum is σ = 11402160. Its totient is φ = 3195936.

The previous prime is 6991463. The next prime is 6991493. The reversal of 6991478 is 8741996.

It is an interprime number because it is at equal distance from previous prime (6991463) and next prime (6991493).

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, 1601 + ... + 4067.

It is an arithmetic number, because the mean of its divisors is an integer number (712635).

Almost surely, 2^6991478 is an apocalyptic number.

6991478 is a deficient number, since it is larger than the sum of its proper divisors (4410682).

6991478 is a wasteful number, since it uses less digits than its factorization.

6991478 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2591.

The product of its digits is 108864, while the sum is 44.

The square root of 6991478 is about 2644.1403139773. The cubic root of 6991478 is about 191.2154581843.

The spelling of 6991478 in words is "six million, nine hundred ninety-one thousand, four hundred seventy-eight".