1665000061601 has 2 divisors, whose sum is σ = 1665000061602. Its totient is φ = 1665000061600.

The previous prime is 1665000061561. The next prime is 1665000061609. The reversal of 1665000061601 is 1061600005661.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1553136570001 + 111863491600 = 1246249^2 + 334460^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1665000061601 is a prime.

It is not a weakly prime, because it can be changed into another prime (1665000061609) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 832500030800 + 832500030801.

It is an arithmetic number, because the mean of its divisors is an integer number (832500030801).

Almost surely, 2^{1665000061601} is an apocalyptic number.

It is an amenable number.

1665000061601 is a deficient number, since it is larger than the sum of its proper divisors (1).

1665000061601 is an equidigital number, since it uses as much as digits as its factorization.

1665000061601 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6480, while the sum is 32.

The spelling of 1665000061601 in words is "one trillion, six hundred sixty-five billion, sixty-one thousand, six hundred one".