66904657 has 2 divisors, whose sum is σ = 66904658. Its totient is φ = 66904656.

The previous prime is 66904619. The next prime is 66904667. The reversal of 66904657 is 75640966.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 58430736 + 8473921 = 7644^2 + 2911^2 .

It is a cyclic number.

It is not a de Polignac number, because 66904657 - 2¹¹ = 66902609 is a prime.

It is not a weakly prime, because it can be changed into another prime (66904667) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33452328 + 33452329.

It is an arithmetic number, because the mean of its divisors is an integer number (33452329).

Almost surely, 2^66904657 is an apocalyptic number.

It is an amenable number.

66904657 is a deficient number, since it is larger than the sum of its proper divisors (1).

66904657 is an equidigital number, since it uses as much as digits as its factorization.

66904657 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 272160, while the sum is 43.

The square root of 66904657 is about 8179.5266977986. The cubic root of 66904657 is about 405.9620617806.

The spelling of 66904657 in words is "sixty-six million, nine hundred four thousand, six hundred fifty-seven".