664396861674 has 96 divisors (see below), whose sum is σ = 1664987546880. Its totient is φ = 175189246848.

The previous prime is 664396861657. The next prime is 664396861721. The reversal of 664396861674 is 476168693466.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 21934612 + ... + 21964880.

It is an arithmetic number, because the mean of its divisors is an integer number (17343620280).

Almost surely, 2^664396861674 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 664396861674, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (832493773440).

664396861674 is an abundant number, since it is smaller than the sum of its proper divisors (1000590685206).

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

664396861674 is a wasteful number, since it uses less digits than its factorization.

664396861674 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36044 (or 36037 counting only the distinct ones).

The product of its digits is 188116992, while the sum is 66.

The spelling of 664396861674 in words is "six hundred sixty-four billion, three hundred ninety-six million, eight hundred sixty-one thousand, six hundred seventy-four".