6601661111 has 2 divisors, whose sum is σ = 6601661112. Its totient is φ = 6601661110.

The previous prime is 6601661047. The next prime is 6601661137. The reversal of 6601661111 is 1111661066.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 6601661111 - 2⁶ = 6601661047 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6691661111) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3300830555 + 3300830556.

It is an arithmetic number, because the mean of its divisors is an integer number (3300830556).

Almost surely, 2^6601661111 is an apocalyptic number.

6601661111 is a deficient number, since it is larger than the sum of its proper divisors (1).

6601661111 is an equidigital number, since it uses as much as digits as its factorization.

6601661111 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1296, while the sum is 29.

The square root of 6601661111 is about 81250.6068346569. The cubic root of 6601661111 is about 1875.9348095687.

The spelling of 6601661111 in words is "six billion, six hundred one million, six hundred sixty-one thousand, one hundred eleven".