66591489 has 4 divisors (see below), whose sum is σ = 88788656. Its totient is φ = 44394324.

The previous prime is 66591467. The next prime is 66591521. The reversal of 66591489 is 98419566.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 66591489 - 2⁹ = 66590977 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (66591439) 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, 11098579 + ... + 11098584.

It is an arithmetic number, because the mean of its divisors is an integer number (22197164).

Almost surely, 2^66591489 is an apocalyptic number.

It is an amenable number.

66591489 is a deficient number, since it is larger than the sum of its proper divisors (22197167).

66591489 is a wasteful number, since it uses less digits than its factorization.

66591489 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22197166.

The product of its digits is 466560, while the sum is 48.

The square root of 66591489 is about 8160.3608376101. The cubic root of 66591489 is about 405.3276604598.

The spelling of 66591489 in words is "sixty-six million, five hundred ninety-one thousand, four hundred eighty-nine".