6991920 has 200 divisors, whose sum is σ = 26467056. Its totient is φ = 1700352.

The previous prime is 6991903. The next prime is 6991939. The reversal of 6991920 is 291996.

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

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 84199 + ... + 84281.

Almost surely, 2^6991920 is an apocalyptic number.

6991920 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 6991920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (13233528).

6991920 is an abundant number, since it is smaller than the sum of its proper divisors (19475136).

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

6991920 is a wasteful number, since it uses less digits than its factorization.

6991920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 121 (or 106 counting only the distinct ones).

The product of its (nonzero) digits is 8748, while the sum is 36.

The square root of 6991920 is about 2644.2238936974. The cubic root of 6991920 is about 191.2194876351.

The spelling of 6991920 in words is "six million, nine hundred ninety-one thousand, nine hundred twenty".