1661506611053 has 2 divisors, whose sum is σ = 1661506611054. Its totient is φ = 1661506611052.

The previous prime is 1661506611041. The next prime is 1661506611109. The reversal of 1661506611053 is 3501166051661.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 980917910569 + 680588700484 = 990413^2 + 824978^2 .

It is a cyclic number.

It is not a de Polignac number, because 1661506611053 - 2⁶ = 1661506610989 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1661506611053.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1661506610053) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 830753305526 + 830753305527.

It is an arithmetic number, because the mean of its divisors is an integer number (830753305527).

Almost surely, 2^{1661506611053} is an apocalyptic number.

It is an amenable number.

1661506611053 is a deficient number, since it is larger than the sum of its proper divisors (1).

1661506611053 is an equidigital number, since it uses as much as digits as its factorization.

1661506611053 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 97200, while the sum is 41.

The spelling of 1661506611053 in words is "one trillion, six hundred sixty-one billion, five hundred six million, six hundred eleven thousand, fifty-three".