665155505 has 16 divisors (see below), whose sum is σ = 934464384. Its totient is φ = 444981120.

The previous prime is 665155501. The next prime is 665155507. The reversal of 665155505 is 505551566.

It is not a de Polignac number, because 665155505 - 2² = 665155501 is a prime.

It is not an unprimeable number, because it can be changed into a prime (665155501) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 230327 + ... + 233196.

It is an arithmetic number, because the mean of its divisors is an integer number (58404024).

Almost surely, 2^665155505 is an apocalyptic number.

It is an amenable number.

665155505 is a deficient number, since it is larger than the sum of its proper divisors (269308879).

665155505 is a wasteful number, since it uses less digits than its factorization.

665155505 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 463576.

The product of its (nonzero) digits is 112500, while the sum is 38.

The square root of 665155505 is about 25790.6088528363. The cubic root of 665155505 is about 872.9199047226.

The spelling of 665155505 in words is "six hundred sixty-five million, one hundred fifty-five thousand, five hundred five".