665499999977 has 2 divisors, whose sum is σ = 665499999978. Its totient is φ = 665499999976.

The previous prime is 665499999919. The next prime is 665500000037. The reversal of 665499999977 is 779999994566.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 646819671001 + 18680328976 = 804251^2 + 136676^2 .

It is a cyclic number.

It is not a de Polignac number, because 665499999977 - 2²⁰ = 665498951401 is a prime.

It is a super-3 number, since 3×665499999977³ (a number of 36 digits) contains 333 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 665499999892 and 665499999901.

It is not a weakly prime, because it can be changed into another prime (665499999907) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 332749999988 + 332749999989.

It is an arithmetic number, because the mean of its divisors is an integer number (332749999989).

Almost surely, 2^665499999977 is an apocalyptic number.

It is an amenable number.

665499999977 is a deficient number, since it is larger than the sum of its proper divisors (1).

665499999977 is an equidigital number, since it uses as much as digits as its factorization.

665499999977 is an evil number, because the sum of its binary digits is even.

The product of its digits is 18749238480, while the sum is 89.

The spelling of 665499999977 in words is "six hundred sixty-five billion, four hundred ninety-nine million, nine hundred ninety-nine thousand, nine hundred seventy-seven".