620546011661 has 2 divisors, whose sum is σ = 620546011662. Its totient is φ = 620546011660.

The previous prime is 620546011601. The next prime is 620546011691. The reversal of 620546011661 is 166110645026.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 396988204900 + 223557806761 = 630070^2 + 472819^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-620546011661 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (620546011601) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 310273005830 + 310273005831.

It is an arithmetic number, because the mean of its divisors is an integer number (310273005831).

Almost surely, 2^620546011661 is an apocalyptic number.

It is an amenable number.

620546011661 is a deficient number, since it is larger than the sum of its proper divisors (1).

620546011661 is an equidigital number, since it uses as much as digits as its factorization.

620546011661 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 51840, while the sum is 38.

Adding to 620546011661 its reverse (166110645026), we get a palindrome (786656656687).

The spelling of 620546011661 in words is "six hundred twenty billion, five hundred forty-six million, eleven thousand, six hundred sixty-one".