66923173 has 2 divisors, whose sum is σ = 66923174. Its totient is φ = 66923172.

The previous prime is 66923167. The next prime is 66923177. The reversal of 66923173 is 37132966.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 60481729 + 6441444 = 7777^2 + 2538^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-66923173 is a prime.

It is a super-2 number, since 2×66923173² = 8957422168775858, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66923177) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33461586 + 33461587.

It is an arithmetic number, because the mean of its divisors is an integer number (33461587).

Almost surely, 2^66923173 is an apocalyptic number.

It is an amenable number.

66923173 is a deficient number, since it is larger than the sum of its proper divisors (1).

66923173 is an equidigital number, since it uses as much as digits as its factorization.

66923173 is an evil number, because the sum of its binary digits is even.

The product of its digits is 40824, while the sum is 37.

The square root of 66923173 is about 8180.6584698299. The cubic root of 66923173 is about 405.9995086019. Note that the first 3 decimals are identical.

The spelling of 66923173 in words is "sixty-six million, nine hundred twenty-three thousand, one hundred seventy-three".