665346261 has 8 divisors (see below), whose sum is σ = 887248384. Its totient is φ = 443504160.

The previous prime is 665346257. The next prime is 665346263. The reversal of 665346261 is 162643566.

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

It is not a de Polignac number, because 665346261 - 2² = 665346257 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (665346263) 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, 31116 + ... + 47946.

It is an arithmetic number, because the mean of its divisors is an integer number (110906048).

Almost surely, 2^665346261 is an apocalyptic number.

It is an amenable number.

665346261 is a deficient number, since it is larger than the sum of its proper divisors (221902123).

665346261 is a wasteful number, since it uses less digits than its factorization.

665346261 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30011.

The product of its digits is 155520, while the sum is 39.

The square root of 665346261 is about 25794.3067555614. The cubic root of 665346261 is about 873.0033432532.

The spelling of 665346261 in words is "six hundred sixty-five million, three hundred forty-six thousand, two hundred sixty-one".