66167771 has 4 divisors (see below), whose sum is σ = 66612000. Its totient is φ = 65723544.

The previous prime is 66167767. The next prime is 66167779. The reversal of 66167771 is 17776166.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 17776166 = 2 ⋅8888083.

It is a cyclic number.

It is not a de Polignac number, because 66167771 - 2² = 66167767 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66167779) 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 3 ways as a sum of consecutive naturals, for example, 221891 + ... + 222188.

It is an arithmetic number, because the mean of its divisors is an integer number (16653000).

Almost surely, 2^66167771 is an apocalyptic number.

66167771 is a deficient number, since it is larger than the sum of its proper divisors (444229).

66167771 is a wasteful number, since it uses less digits than its factorization.

66167771 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 444228.

The product of its digits is 74088, while the sum is 41.

The square root of 66167771 is about 8134.3574423552. The cubic root of 66167771 is about 404.4661380210.

The spelling of 66167771 in words is "sixty-six million, one hundred sixty-seven thousand, seven hundred seventy-one".