664194030361 has 9 divisors (see below), whose sum is σ = 677006472541. Its totient is φ = 651619688512.

The previous prime is 664194030349. The next prime is 664194030371. The reversal of 664194030361 is 163030491466.

The square root of 664194030361 is 814981.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 469130474761 + 195063555600 = 684931^2 + 441660^2 .

It is not a de Polignac number, because 664194030361 - 2²⁵ = 664160475929 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (664194030371) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 43186305 + ... + 43201681.

Almost surely, 2^664194030361 is an apocalyptic number.

664194030361 is the 814981-st square number.

664194030361 is the 407491-st centered octagonal number.

It is an amenable number.

664194030361 is a deficient number, since it is larger than the sum of its proper divisors (12812442180).

664194030361 is an frugal number, since it uses more digits than its factorization.

664194030361 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30860 (or 15430 counting only the distinct ones).

The product of its (nonzero) digits is 279936, while the sum is 43.

The spelling of 664194030361 in words is "six hundred sixty-four billion, one hundred ninety-four million, thirty thousand, three hundred sixty-one".