665740255 has 4 divisors (see below), whose sum is σ = 798888312. Its totient is φ = 532592200.

The previous prime is 665740249. The next prime is 665740277. The reversal of 665740255 is 552047566.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 665740255 - 2⁹ = 665739743 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 66574021 + ... + 66574030.

It is an arithmetic number, because the mean of its divisors is an integer number (199722078).

Almost surely, 2^665740255 is an apocalyptic number.

665740255 is a deficient number, since it is larger than the sum of its proper divisors (133148057).

665740255 is a wasteful number, since it uses less digits than its factorization.

665740255 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 133148056.

The product of its (nonzero) digits is 252000, while the sum is 40.

The square root of 665740255 is about 25801.9428532039. The cubic root of 665740255 is about 873.1756295892.

The spelling of 665740255 in words is "six hundred sixty-five million, seven hundred forty thousand, two hundred fifty-five".