664761611 has 2 divisors, whose sum is σ = 664761612. Its totient is φ = 664761610.

The previous prime is 664761593. The next prime is 664761667. The reversal of 664761611 is 116167466.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 664761611 - 2¹⁰ = 664760587 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (664761011) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 332380805 + 332380806.

It is an arithmetic number, because the mean of its divisors is an integer number (332380806).

Almost surely, 2^664761611 is an apocalyptic number.

664761611 is a deficient number, since it is larger than the sum of its proper divisors (1).

664761611 is an equidigital number, since it uses as much as digits as its factorization.

664761611 is an evil number, because the sum of its binary digits is even.

The product of its digits is 36288, while the sum is 38.

The square root of 664761611 is about 25782.9713376872. The cubic root of 664761611 is about 872.7475611606.

The spelling of 664761611 in words is "six hundred sixty-four million, seven hundred sixty-one thousand, six hundred eleven".