665210655 has 24 divisors (see below), whose sum is σ = 1153683648. Its totient is φ = 354578496.

The previous prime is 665210641. The next prime is 665210681. The reversal of 665210655 is 556012566.

It is a happy number.

It is not a de Polignac number, because 665210655 - 2²² = 661016351 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 111529 + ... + 117341.

It is an arithmetic number, because the mean of its divisors is an integer number (48070152).

Almost surely, 2^665210655 is an apocalyptic number.

665210655 is a deficient number, since it is larger than the sum of its proper divisors (488472993).

665210655 is a wasteful number, since it uses less digits than its factorization.

665210655 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8367 (or 8364 counting only the distinct ones).

The product of its (nonzero) digits is 54000, while the sum is 36.

The square root of 665210655 is about 25791.6780183066. The cubic root of 665210655 is about 872.9440295084.

The spelling of 665210655 in words is "six hundred sixty-five million, two hundred ten thousand, six hundred fifty-five".