66945123 has 60 divisors (see below), whose sum is σ = 118186992. Its totient is φ = 37648800.

The previous prime is 66945107. The next prime is 66945163. The reversal of 66945123 is 32154966.

It is a happy number.

It is a Cunningham number, because it is equal to 8182²-1.

It is not a de Polignac number, because 66945123 - 2⁴ = 66945107 is a prime.

It is not an unprimeable number, because it can be changed into a prime (66945103) by changing a digit.

It is a polite number, since it can be written in 59 ways as a sum of consecutive naturals, for example, 400786 + ... + 400952.

Almost surely, 2^66945123 is an apocalyptic number.

66945123 is a gapful number since it is divisible by the number (63) formed by its first and last digit.

66945123 is a deficient number, since it is larger than the sum of its proper divisors (51241869).

66945123 is a wasteful number, since it uses less digits than its factorization.

66945123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 294 (or 278 counting only the distinct ones).

The product of its digits is 38880, while the sum is 36.

The square root of 66945123 is about 8181.9999388902. Note that the first 4 decimals coincide. The cubic root of 66945123 is about 406.0438914102.

The spelling of 66945123 in words is "sixty-six million, nine hundred forty-five thousand, one hundred twenty-three".