665637863552 has 64 divisors (see below), whose sum is σ = 1342043367840. Its totient is φ = 328823070720.

The previous prime is 665637863521. The next prime is 665637863593. The reversal of 665637863552 is 255368736566.

It is a tau number, because it is divible by the number of its divisors (64).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7242527 + ... + 7333857.

Almost surely, 2^665637863552 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 665637863552, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (671021683920).

665637863552 is an abundant number, since it is smaller than the sum of its proper divisors (676405504288).

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

665637863552 is an equidigital number, since it uses as much as digits as its factorization.

665637863552 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 92029 (or 92017 counting only the distinct ones).

The product of its digits is 163296000, while the sum is 62.

The spelling of 665637863552 in words is "six hundred sixty-five billion, six hundred thirty-seven million, eight hundred sixty-three thousand, five hundred fifty-two".