6691072788 has 18 divisors (see below), whose sum is σ = 16913545194. Its totient is φ = 2230357584.

The previous prime is 6691072769. The next prime is 6691072811. The reversal of 6691072788 is 8872701966.

It can be written as a sum of positive squares in only one way, i.e., 5789992464 + 901080324 = 76092^2 + 30018^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 92931531 + ... + 92931602.

Almost surely, 2^6691072788 is an apocalyptic number.

It is an amenable number.

6691072788 is an abundant number, since it is smaller than the sum of its proper divisors (10222472406).

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

6691072788 is a wasteful number, since it uses less digits than its factorization.

6691072788 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 185863143 (or 185863138 counting only the distinct ones).

The product of its (nonzero) digits is 2032128, while the sum is 54.

The square root of 6691072788 is about 81798.9779153750. The cubic root of 6691072788 is about 1884.3659647166.

The spelling of 6691072788 in words is "six billion, six hundred ninety-one million, seventy-two thousand, seven hundred eighty-eight".