66057977 has 4 divisors (see below), whose sum is σ = 66098340. Its totient is φ = 66017616.

The previous prime is 66057967. The next prime is 66057991. The reversal of 66057977 is 77975066.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 8737936 + 57320041 = 2956^2 + 7571^2 .

It is a cyclic number.

It is not a de Polignac number, because 66057977 - 2⁴ = 66057961 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66057947) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 17618 + ... + 21035.

It is an arithmetic number, because the mean of its divisors is an integer number (16524585).

Almost surely, 2^66057977 is an apocalyptic number.

It is an amenable number.

66057977 is a deficient number, since it is larger than the sum of its proper divisors (40363).

66057977 is a wasteful number, since it uses less digits than its factorization.

66057977 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40362.

The product of its (nonzero) digits is 555660, while the sum is 47.

The square root of 66057977 is about 8127.6058590461. The cubic root of 66057977 is about 404.2423002442.

The spelling of 66057977 in words is "sixty-six million, fifty-seven thousand, nine hundred seventy-seven".