111111503500661 has 2 divisors, whose sum is σ = 111111503500662. Its totient is φ = 111111503500660.

The previous prime is 111111503500651. The next prime is 111111503500691. The reversal of 111111503500661 is 166005305111111.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 60720032797636 + 50391470703025 = 7792306^2 + 7098695^2 .

It is a cyclic number.

It is not a de Polignac number, because 111111503500661 - 2³⁸ = 110836625593717 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (111111503500651) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 55555751750330 + 55555751750331.

It is an arithmetic number, because the mean of its divisors is an integer number (55555751750331).

Almost surely, 2^{111111503500661} is an apocalyptic number.

It is an amenable number.

111111503500661 is a deficient number, since it is larger than the sum of its proper divisors (1).

111111503500661 is an equidigital number, since it uses as much as digits as its factorization.

111111503500661 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2700, while the sum is 32.

Adding to 111111503500661 its reverse (166005305111111), we get a palindrome (277116808611772).

The spelling of 111111503500661 in words is "one hundred eleven trillion, one hundred eleven billion, five hundred three million, five hundred thousand, six hundred sixty-one".