664139741 has 4 divisors (see below), whose sum is σ = 670715484. Its totient is φ = 657564000.

The previous prime is 664139713. The next prime is 664139747. The reversal of 664139741 is 147931466.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 554414116 + 109725625 = 23546^2 + 10475^2 .

It is a cyclic number.

It is not a de Polignac number, because 664139741 - 2¹⁴ = 664123357 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (664139747) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3287720 + ... + 3287921.

It is an arithmetic number, because the mean of its divisors is an integer number (167678871).

Almost surely, 2^664139741 is an apocalyptic number.

It is an amenable number.

664139741 is a deficient number, since it is larger than the sum of its proper divisors (6575743).

664139741 is a wasteful number, since it uses less digits than its factorization.

664139741 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6575742.

The product of its digits is 108864, while the sum is 41.

The square root of 664139741 is about 25770.9088120695. The cubic root of 664139741 is about 872.4753308132.

The spelling of 664139741 in words is "six hundred sixty-four million, one hundred thirty-nine thousand, seven hundred forty-one".