660320533 has 4 divisors (see below), whose sum is σ = 661825120. Its totient is φ = 658815948.

The previous prime is 660320417. The next prime is 660320543. The reversal of 660320533 is 335023066.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 660320533 - 2⁹ = 660320021 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (660320543) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 751635 + ... + 752512.

It is an arithmetic number, because the mean of its divisors is an integer number (165456280).

Almost surely, 2^660320533 is an apocalyptic number.

It is an amenable number.

660320533 is a deficient number, since it is larger than the sum of its proper divisors (1504587).

660320533 is a wasteful number, since it uses less digits than its factorization.

660320533 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1504586.

The product of its (nonzero) digits is 9720, while the sum is 28.

The square root of 660320533 is about 25696.7027651409. The cubic root of 660320533 is about 870.7996932089.

Adding to 660320533 its reverse (335023066), we get a palindrome (995343599).

The spelling of 660320533 in words is "six hundred sixty million, three hundred twenty thousand, five hundred thirty-three".