11503135661 has 2 divisors, whose sum is σ = 11503135662. Its totient is φ = 11503135660.

The previous prime is 11503135639. The next prime is 11503135691. The reversal of 11503135661 is 16653130511.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 8557360036 + 2945775625 = 92506^2 + 54275^2 .

It is an emirp because it is prime and its reverse (16653130511) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 11503135661 - 2²² = 11498941357 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (11503135691) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5751567830 + 5751567831.

It is an arithmetic number, because the mean of its divisors is an integer number (5751567831).

Almost surely, 2^11503135661 is an apocalyptic number.

It is an amenable number.

11503135661 is a deficient number, since it is larger than the sum of its proper divisors (1).

11503135661 is an equidigital number, since it uses as much as digits as its factorization.

11503135661 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 8100, while the sum is 32.

The spelling of 11503135661 in words is "eleven billion, five hundred three million, one hundred thirty-five thousand, six hundred sixty-one".