664628761732660 has 24 divisors (see below), whose sum is σ = 1395760940176680. Its totient is φ = 265843782685824.

The previous prime is 664628761732651. The next prime is 664628761732673. The reversal of 664628761732660 is 66237167826466.

It can be written as a sum of positive squares in 4 ways, for example, as 65105113863076 + 599523647869584 = 8068774^2 + 24485172^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 664628761732660.

It is a congruent number.

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, 481919659 + ... + 483296818.

It is an arithmetic number, because the mean of its divisors is an integer number (58156705840695).

Almost surely, 2^{664628761732660} is an apocalyptic number.

It is an amenable number.

664628761732660 is an abundant number, since it is smaller than the sum of its proper divisors (731132178444020).

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

664628761732660 is a wasteful number, since it uses less digits than its factorization.

664628761732660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 965250915 (or 965250913 counting only the distinct ones).

The product of its (nonzero) digits is 877879296, while the sum is 70.

The spelling of 664628761732660 in words is "six hundred sixty-four trillion, six hundred twenty-eight billion, seven hundred sixty-one million, seven hundred thirty-two thousand, six hundred sixty".