665356653523 has 2 divisors, whose sum is σ = 665356653524. Its totient is φ = 665356653522.

The previous prime is 665356653517. The next prime is 665356653569. The reversal of 665356653523 is 325356653566.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 665356653523 - 2¹⁷ = 665356522451 is a prime.

It is not a weakly prime, because it can be changed into another prime (665356653023) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 332678326761 + 332678326762.

It is an arithmetic number, because the mean of its divisors is an integer number (332678326762).

Almost surely, 2^665356653523 is an apocalyptic number.

665356653523 is a deficient number, since it is larger than the sum of its proper divisors (1).

665356653523 is an equidigital number, since it uses as much as digits as its factorization.

665356653523 is an evil number, because the sum of its binary digits is even.

The product of its digits is 43740000, while the sum is 55.

The spelling of 665356653523 in words is "six hundred sixty-five billion, three hundred fifty-six million, six hundred fifty-three thousand, five hundred twenty-three".