668753537 has 2 divisors, whose sum is σ = 668753538. Its totient is φ = 668753536.

The previous prime is 668753521. The next prime is 668753573. The reversal of 668753537 is 735357866.

It is a happy number.

Together with next prime (668753573) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 587771536 + 80982001 = 24244^2 + 8999^2 .

It is a cyclic number.

It is not a de Polignac number, because 668753537 - 2⁴ = 668753521 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (668753237) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 334376768 + 334376769.

It is an arithmetic number, because the mean of its divisors is an integer number (334376769).

Almost surely, 2^668753537 is an apocalyptic number.

It is an amenable number.

668753537 is a deficient number, since it is larger than the sum of its proper divisors (1).

668753537 is an equidigital number, since it uses as much as digits as its factorization.

668753537 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3175200, while the sum is 50.

The square root of 668753537 is about 25860.2694688203. The cubic root of 668753537 is about 874.4910398479.

The spelling of 668753537 in words is "six hundred sixty-eight million, seven hundred fifty-three thousand, five hundred thirty-seven".