665355331553 has 24 divisors (see below), whose sum is σ = 733744248384. Its totient is φ = 602883721440.

The previous prime is 665355331547. The next prime is 665355331561. The reversal of 665355331553 is 355133553566.

665355331553 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 665355331553 - 2¹⁴ = 665355315169 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (665355331523) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 56974151 + ... + 56985827.

It is an arithmetic number, because the mean of its divisors is an integer number (30572677016).

Almost surely, 2^665355331553 is an apocalyptic number.

It is an amenable number.

665355331553 is a deficient number, since it is larger than the sum of its proper divisors (68388916831).

665355331553 is a wasteful number, since it uses less digits than its factorization.

665355331553 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13205 (or 13194 counting only the distinct ones).

The product of its digits is 9112500, while the sum is 50.

The spelling of 665355331553 in words is "six hundred sixty-five billion, three hundred fifty-five million, three hundred thirty-one thousand, five hundred fifty-three".