665613481 has 8 divisors (see below), whose sum is σ = 741532680. Its totient is φ = 593225472.

The previous prime is 665613479. The next prime is 665613497. The reversal of 665613481 is 184316566.

It can be written as a sum of positive squares in 4 ways, for example, as 182493081 + 483120400 = 13509^2 + 21980^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 665613481 - 2¹ = 665613479 is a prime.

It is a super-2 number, since 2×665613481² = 886082612177874722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (665613401) 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, 882400 + ... + 883153.

It is an arithmetic number, because the mean of its divisors is an integer number (92691585).

Almost surely, 2^665613481 is an apocalyptic number.

It is an amenable number.

665613481 is a deficient number, since it is larger than the sum of its proper divisors (75919199).

665613481 is a wasteful number, since it uses less digits than its factorization.

665613481 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1765595.

The product of its digits is 103680, while the sum is 40.

The square root of 665613481 is about 25799.4860607726. The cubic root of 665613481 is about 873.1202010675.

The spelling of 665613481 in words is "six hundred sixty-five million, six hundred thirteen thousand, four hundred eighty-one".