6991655598 has 48 divisors (see below), whose sum is σ = 15815723040. Its totient is φ = 2228024832.

The previous prime is 6991655597. The next prime is 6991655599. The reversal of 6991655598 is 8955561996.

6991655598 is a `hidden beast` number, since 69 + 9 + 16 + 5 + 559 + 8 = 666.

It is an interprime number because it is at equal distance from previous prime (6991655597) and next prime (6991655599).

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6991655597) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1076890 + ... + 1083362.

It is an arithmetic number, because the mean of its divisors is an integer number (329494230).

Almost surely, 2^6991655598 is an apocalyptic number.

6991655598 is an abundant number, since it is smaller than the sum of its proper divisors (8824067442).

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

6991655598 is a wasteful number, since it uses less digits than its factorization.

6991655598 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9113 (or 9110 counting only the distinct ones).

The product of its digits is 26244000, while the sum is 63.

The square root of 6991655598 is about 83616.1204433691. The cubic root of 6991655598 is about 1912.1707725992.

The spelling of 6991655598 in words is "six billion, nine hundred ninety-one million, six hundred fifty-five thousand, five hundred ninety-eight".