665357145720 has 64 divisors (see below), whose sum is σ = 2050019327520. Its totient is φ = 172633204224.

The previous prime is 665357145709. The next prime is 665357145721. The reversal of 665357145720 is 27541753566.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (665357145721) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 74923167 + ... + 74932046.

Almost surely, 2^665357145720 is an apocalyptic number.

665357145720 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

665357145720 is an abundant number, since it is smaller than the sum of its proper divisors (1384662181800).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

665357145720 is a wasteful number, since it uses less digits than its factorization.

665357145720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 149855264 (or 149855260 counting only the distinct ones).

The product of its (nonzero) digits is 5292000, while the sum is 51.

The spelling of 665357145720 in words is "six hundred sixty-five billion, three hundred fifty-seven million, one hundred forty-five thousand, seven hundred twenty".