66173641 has 2 divisors, whose sum is σ = 66173642. Its totient is φ = 66173640.

The previous prime is 66173587. The next prime is 66173651. The reversal of 66173641 is 14637166.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 63680400 + 2493241 = 7980^2 + 1579^2 .

It is a cyclic number.

It is not a de Polignac number, because 66173641 - 2¹¹ = 66171593 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 66173597 and 66173606.

It is not a weakly prime, because it can be changed into another prime (66173651) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33086820 + 33086821.

It is an arithmetic number, because the mean of its divisors is an integer number (33086821).

Almost surely, 2^66173641 is an apocalyptic number.

It is an amenable number.

66173641 is a deficient number, since it is larger than the sum of its proper divisors (1).

66173641 is an equidigital number, since it uses as much as digits as its factorization.

66173641 is an evil number, because the sum of its binary digits is even.

The product of its digits is 18144, while the sum is 34.

The square root of 66173641 is about 8134.7182495769. The cubic root of 66173641 is about 404.4780982548.

The spelling of 66173641 in words is "sixty-six million, one hundred seventy-three thousand, six hundred forty-one".