66123081 has 32 divisors (see below), whose sum is σ = 105235200. Its totient is φ = 40884480.

The previous prime is 66123077. The next prime is 66123089. The reversal of 66123081 is 18032166.

It is not a de Polignac number, because 66123081 - 2² = 66123077 is a prime.

It is a super-2 number, since 2×66123081² = 8744523681865122, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (66123089) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 31575 + ... + 33603.

It is an arithmetic number, because the mean of its divisors is an integer number (3288600).

Almost surely, 2^66123081 is an apocalyptic number.

It is an amenable number.

66123081 is a deficient number, since it is larger than the sum of its proper divisors (39112119).

66123081 is a wasteful number, since it uses less digits than its factorization.

66123081 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2126 (or 2120 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 27.

The square root of 66123081 is about 8131.6099881881. The cubic root of 66123081 is about 404.3750581171.

The spelling of 66123081 in words is "sixty-six million, one hundred twenty-three thousand, eighty-one".