66390629 has 2 divisors, whose sum is σ = 66390630. Its totient is φ = 66390628.

The previous prime is 66390613. The next prime is 66390679. The reversal of 66390629 is 92609366.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 65642404 + 748225 = 8102^2 + 865^2 .

It is a cyclic number.

It is not a de Polignac number, because 66390629 - 2⁴ = 66390613 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66390679) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33195314 + 33195315.

It is an arithmetic number, because the mean of its divisors is an integer number (33195315).

Almost surely, 2^66390629 is an apocalyptic number.

It is an amenable number.

66390629 is a deficient number, since it is larger than the sum of its proper divisors (1).

66390629 is an equidigital number, since it uses as much as digits as its factorization.

66390629 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 104976, while the sum is 41.

The square root of 66390629 is about 8148.0444893238. The cubic root of 66390629 is about 404.9197199004.

The spelling of 66390629 in words is "sixty-six million, three hundred ninety thousand, six hundred twenty-nine".