66511057 has 8 divisors (see below), whose sum is σ = 67473000. Its totient is φ = 65554944.

The previous prime is 66511033. The next prime is 66511069. The reversal of 66511057 is 75011566.

It can be written as a sum of positive squares in 4 ways, for example, as 8156736 + 58354321 = 2856^2 + 7639^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 66511057 - 2¹⁵ = 66478289 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66511087) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 24819 + ... + 27367.

It is an arithmetic number, because the mean of its divisors is an integer number (8434125).

Almost surely, 2^66511057 is an apocalyptic number.

It is an amenable number.

66511057 is a deficient number, since it is larger than the sum of its proper divisors (961943).

66511057 is a wasteful number, since it uses less digits than its factorization.

66511057 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2915.

The product of its (nonzero) digits is 6300, while the sum is 31.

The square root of 66511057 is about 8155.4311351393. The cubic root of 66511057 is about 405.1644041166.

The spelling of 66511057 in words is "sixty-six million, five hundred eleven thousand, fifty-seven".