664618739 has 2 divisors, whose sum is σ = 664618740. Its totient is φ = 664618738.

The previous prime is 664618711. The next prime is 664618763. The reversal of 664618739 is 937816466.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 664618739 - 2⁸ = 664618483 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (664618709) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 332309369 + 332309370.

It is an arithmetic number, because the mean of its divisors is an integer number (332309370).

Almost surely, 2^664618739 is an apocalyptic number.

664618739 is a deficient number, since it is larger than the sum of its proper divisors (1).

664618739 is an equidigital number, since it uses as much as digits as its factorization.

664618739 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1306368, while the sum is 50.

The square root of 664618739 is about 25780.2005228819. The cubic root of 664618739 is about 872.6850324177.

The spelling of 664618739 in words is "six hundred sixty-four million, six hundred eighteen thousand, seven hundred thirty-nine".