66512889 has 6 divisors (see below), whose sum is σ = 96074186. Its totient is φ = 44341920.

The previous prime is 66512881. The next prime is 66512899. The reversal of 66512889 is 98821566.

It can be written as a sum of positive squares in only one way, i.e., 63680400 + 2832489 = 7980^2 + 1683^2 .

It is not a de Polignac number, because 66512889 - 2³ = 66512881 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66512881) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 3695152 + ... + 3695169.

Almost surely, 2^66512889 is an apocalyptic number.

It is an amenable number.

66512889 is a deficient number, since it is larger than the sum of its proper divisors (29561297).

66512889 is a wasteful number, since it uses less digits than its factorization.

66512889 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7390327 (or 7390324 counting only the distinct ones).

The product of its digits is 207360, while the sum is 45.

The square root of 66512889 is about 8155.5434521557. The cubic root of 66512889 is about 405.1681240714.

The spelling of 66512889 in words is "sixty-six million, five hundred twelve thousand, eight hundred eighty-nine".