6991880 has 32 divisors (see below), whose sum is σ = 17979840. Its totient is φ = 2397120.

The previous prime is 6991877. The next prime is 6991889. The reversal of 6991880 is 881996.

It is a Smith number, since the sum of its digits (41) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (6991889) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12206 + ... + 12765.

It is an arithmetic number, because the mean of its divisors is an integer number (561870).

Almost surely, 2^6991880 is an apocalyptic number.

It is an amenable number.

6991880 is an abundant number, since it is smaller than the sum of its proper divisors (10987960).

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

6991880 is a wasteful number, since it uses less digits than its factorization.

6991880 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24989 (or 24985 counting only the distinct ones).

The product of its (nonzero) digits is 31104, while the sum is 41.

The square root of 6991880 is about 2644.2163300305. The cubic root of 6991880 is about 191.2191229859.

The spelling of 6991880 in words is "six million, nine hundred ninety-one thousand, eight hundred eighty".