66205457 has 4 divisors (see below), whose sum is σ = 66791460. Its totient is φ = 65619456.

The previous prime is 66205453. The next prime is 66205483. The reversal of 66205457 is 75450266.

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 2588881 + 63616576 = 1609^2 + 7976^2 .

It is a cyclic number.

It is not a de Polignac number, because 66205457 - 2² = 66205453 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66205453) 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, 292832 + ... + 293057.

It is an arithmetic number, because the mean of its divisors is an integer number (16697865).

Almost surely, 2^66205457 is an apocalyptic number.

It is an amenable number.

66205457 is a deficient number, since it is larger than the sum of its proper divisors (586003).

66205457 is a wasteful number, since it uses less digits than its factorization.

66205457 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 586002.

The product of its (nonzero) digits is 50400, while the sum is 35.

The square root of 66205457 is about 8136.6735832280. The cubic root of 66205457 is about 404.5429116412.

The spelling of 66205457 in words is "sixty-six million, two hundred five thousand, four hundred fifty-seven".