1616640241661 has 2 divisors, whose sum is σ = 1616640241662. Its totient is φ = 1616640241660.

The previous prime is 1616640241639. The next prime is 1616640241693. The reversal of 1616640241661 is 1661420466161.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1616635960900 + 4280761 = 1271470^2 + 2069^2 .

It is a cyclic number.

It is not a de Polignac number, because 1616640241661 - 2¹⁰ = 1616640240637 is a prime.

It is a super-2 number, since 2×1616640241661² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1616640241631) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 808320120830 + 808320120831.

It is an arithmetic number, because the mean of its divisors is an integer number (808320120831).

Almost surely, 2^{1616640241661} is an apocalyptic number.

It is an amenable number.

1616640241661 is a deficient number, since it is larger than the sum of its proper divisors (1).

1616640241661 is an equidigital number, since it uses as much as digits as its factorization.

1616640241661 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 248832, while the sum is 44.

The spelling of 1616640241661 in words is "one trillion, six hundred sixteen billion, six hundred forty million, two hundred forty-one thousand, six hundred sixty-one".