664787105523 has 8 divisors (see below), whose sum is σ = 984869786000. Its totient is φ = 443191403664.

The previous prime is 664787105459. The next prime is 664787105561. The reversal of 664787105523 is 325501787466.

664787105523 is a `hidden beast` number, since 6 + 6 + 4 + 7 + 8 + 7 + 105 + 523 = 666.

It is not a de Polignac number, because 664787105523 - 2⁶ = 664787105459 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 664787105523.

It is not an unprimeable number, because it can be changed into a prime (664787104523) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12310872298 + ... + 12310872351.

It is an arithmetic number, because the mean of its divisors is an integer number (123108723250).

Almost surely, 2^664787105523 is an apocalyptic number.

664787105523 is a deficient number, since it is larger than the sum of its proper divisors (320082680477).

664787105523 is a wasteful number, since it uses less digits than its factorization.

664787105523 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24621744658 (or 24621744652 counting only the distinct ones).

The product of its (nonzero) digits is 8467200, while the sum is 54.

The spelling of 664787105523 in words is "six hundred sixty-four billion, seven hundred eighty-seven million, one hundred five thousand, five hundred twenty-three".