66570989 has 2 divisors, whose sum is σ = 66570990. Its totient is φ = 66570988.

The previous prime is 66570961. The next prime is 66570991. The reversal of 66570989 is 98907566.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 46812964 + 19758025 = 6842^2 + 4445^2 .

It is a cyclic number.

It is not a de Polignac number, because 66570989 - 2²⁴ = 49793773 is a prime.

Together with 66570991, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66170989) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33285494 + 33285495.

It is an arithmetic number, because the mean of its divisors is an integer number (33285495).

Almost surely, 2^66570989 is an apocalyptic number.

It is an amenable number.

66570989 is a deficient number, since it is larger than the sum of its proper divisors (1).

66570989 is an equidigital number, since it uses as much as digits as its factorization.

66570989 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 816480, while the sum is 50.

The square root of 66570989 is about 8159.1046690185. The cubic root of 66570989 is about 405.2860632028.

The spelling of 66570989 in words is "sixty-six million, five hundred seventy thousand, nine hundred eighty-nine".