66173803 has 2 divisors, whose sum is σ = 66173804. Its totient is φ = 66173802.

The previous prime is 66173801. The next prime is 66173819. The reversal of 66173803 is 30837166.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 66173803 - 2¹ = 66173801 is a prime.

Together with 66173801, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (66173801) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33086901 + 33086902.

It is an arithmetic number, because the mean of its divisors is an integer number (33086902).

Almost surely, 2^66173803 is an apocalyptic number.

66173803 is a deficient number, since it is larger than the sum of its proper divisors (1).

66173803 is an equidigital number, since it uses as much as digits as its factorization.

66173803 is an evil number, because the sum of its binary digits is even.

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

The square root of 66173803 is about 8134.7282068917. The cubic root of 66173803 is about 404.4784283227.

The spelling of 66173803 in words is "sixty-six million, one hundred seventy-three thousand, eight hundred three".