665653031 has 4 divisors (see below), whose sum is σ = 667780032. Its totient is φ = 663526032.

The previous prime is 665653019. The next prime is 665653033. The reversal of 665653031 is 130356566.

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

It is a cyclic number.

It is not a de Polignac number, because 665653031 - 2¹⁰ = 665652007 is a prime.

It is a super-2 number, since 2×665653031² = 886187915358973922, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 665652982 and 665653000.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (665653033) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1063031 + ... + 1063656.

It is an arithmetic number, because the mean of its divisors is an integer number (166945008).

Almost surely, 2^665653031 is an apocalyptic number.

665653031 is a deficient number, since it is larger than the sum of its proper divisors (2127001).

665653031 is a wasteful number, since it uses less digits than its factorization.

665653031 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2127000.

The product of its (nonzero) digits is 48600, while the sum is 35.

The square root of 665653031 is about 25800.2525375237. The cubic root of 665653031 is about 873.1374939965.

It can be divided in two parts, 66565 and 3031, that added together give a palindrome (69596).

The spelling of 665653031 in words is "six hundred sixty-five million, six hundred fifty-three thousand, thirty-one".