11661783445557 has 32 divisors (see below), whose sum is σ = 19745057653760. Its totient is φ = 6663795551280.

The previous prime is 11661783445553. The next prime is 11661783445567. The reversal of 11661783445557 is 75554438716611.

11661783445557 is a `hidden beast` number, since 1 + 1 + 6 + 6 + 1 + 7 + 8 + 34 + 45 + 557 = 666.

11661783445557 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 11661783445557 - 2² = 11661783445553 is a prime.

It is a Smith number, since the sum of its digits (63) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 11661783445494 and 11661783445503.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11661783445553) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 17539998 + ... + 18192720.

It is an arithmetic number, because the mean of its divisors is an integer number (617033051680).

Almost surely, 2^{11661783445557} is an apocalyptic number.

It is an amenable number.

11661783445557 is a deficient number, since it is larger than the sum of its proper divisors (8083274208203).

11661783445557 is an equidigital number, since it uses as much as digits as its factorization.

11661783445557 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 747270 (or 747264 counting only the distinct ones).

The product of its digits is 84672000, while the sum is 63.

The spelling of 11661783445557 in words is "eleven trillion, six hundred sixty-one billion, seven hundred eighty-three million, four hundred forty-five thousand, five hundred fifty-seven".