61120516111661 has 2 divisors, whose sum is σ = 61120516111662. Its totient is φ = 61120516111660.

The previous prime is 61120516111651. The next prime is 61120516111667. The reversal of 61120516111661 is 16611161502116.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 55307927824900 + 5812588286761 = 7436930^2 + 2410931^2 .

It is a cyclic number.

It is not a de Polignac number, because 61120516111661 - 2¹⁸ = 61120515849517 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (61120516111667) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30560258055830 + 30560258055831.

It is an arithmetic number, because the mean of its divisors is an integer number (30560258055831).

Almost surely, 2^{61120516111661} is an apocalyptic number.

It is an amenable number.

61120516111661 is a deficient number, since it is larger than the sum of its proper divisors (1).

61120516111661 is an equidigital number, since it uses as much as digits as its factorization.

61120516111661 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 12960, while the sum is 38.

Adding to 61120516111661 its reverse (16611161502116), we get a palindrome (77731677613777).

The spelling of 61120516111661 in words is "sixty-one trillion, one hundred twenty billion, five hundred sixteen million, one hundred eleven thousand, six hundred sixty-one".