66021172 has 24 divisors (see below), whose sum is σ = 135613184. Its totient is φ = 27529632.

The previous prime is 66021133. The next prime is 66021173. The reversal of 66021172 is 27112066.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66021173) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 30828 + ... + 32899.

Almost surely, 2^66021172 is an apocalyptic number.

It is an amenable number.

66021172 is an abundant number, since it is smaller than the sum of its proper divisors (69592012).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

66021172 is a wasteful number, since it uses less digits than its factorization.

66021172 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 63775 (or 63773 counting only the distinct ones).

The product of its (nonzero) digits is 1008, while the sum is 25.

The square root of 66021172 is about 8125.3413466758. The cubic root of 66021172 is about 404.1672101361.

The spelling of 66021172 in words is "sixty-six million, twenty-one thousand, one hundred seventy-two".