7728486666 has 32 divisors (see below), whose sum is σ = 15885398400. Its totient is φ = 2504851776.

The previous prime is 7728486617. The next prime is 7728486673. The reversal of 7728486666 is 6666848277.

It is a super-2 number, since 2×7728486666² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 343635 + ... + 365433.

It is an arithmetic number, because the mean of its divisors is an integer number (496418700).

Almost surely, 2^7728486666 is an apocalyptic number.

7728486666 is an abundant number, since it is smaller than the sum of its proper divisors (8156911734).

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

7728486666 is a wasteful number, since it uses less digits than its factorization.

7728486666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23438.

The product of its digits is 32514048, while the sum is 60.

The square root of 7728486666 is about 87911.8118684856. The cubic root of 7728486666 is about 1977.1129800403.

The spelling of 7728486666 in words is "seven billion, seven hundred twenty-eight million, four hundred eighty-six thousand, six hundred sixty-six".