664787083784 has 8 divisors (see below), whose sum is σ = 1246475782110. Its totient is φ = 332393541888.

The previous prime is 664787083759. The next prime is 664787083789. The reversal of 664787083784 is 487380787466.

It can be written as a sum of positive squares in only one way, i.e., 344125370884 + 320661712900 = 586622^2 + 566270^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is not an unprimeable number, because it can be changed into a prime (664787083789) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 41549192729 + ... + 41549192744.

Almost surely, 2^664787083784 is an apocalyptic number.

It is an amenable number.

664787083784 is a deficient number, since it is larger than the sum of its proper divisors (581688698326).

664787083784 is a wasteful number, since it uses less digits than its factorization.

664787083784 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 83098385479 (or 83098385475 counting only the distinct ones).

The product of its (nonzero) digits is 303464448, while the sum is 68.

The spelling of 664787083784 in words is "six hundred sixty-four billion, seven hundred eighty-seven million, eighty-three thousand, seven hundred eighty-four".