666988763 has 8 divisors (see below), whose sum is σ = 765692928. Its totient is φ = 569139624.

The previous prime is 666988741. The next prime is 666988771. The reversal of 666988763 is 367889666.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 666988763 - 2²⁶ = 599879899 is a prime.

It is a super-3 number, since 3×666988763³ (a number of 27 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (666988463) 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, 212081 + ... + 215202.

It is an arithmetic number, because the mean of its divisors is an integer number (95711616).

Almost surely, 2^666988763 is an apocalyptic number.

666988763 is a deficient number, since it is larger than the sum of its proper divisors (98704165).

666988763 is a wasteful number, since it uses less digits than its factorization.

666988763 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 427513.

The product of its digits is 15676416, while the sum is 59.

The square root of 666988763 is about 25826.1255901848. The cubic root of 666988763 is about 873.7211306170.

The spelling of 666988763 in words is "six hundred sixty-six million, nine hundred eighty-eight thousand, seven hundred sixty-three".