66465591 has 16 divisors (see below), whose sum is σ = 94199040. Its totient is φ = 41567040.

The previous prime is 66465589. The next prime is 66465611. The reversal of 66465591 is 19556466.

It is not a de Polignac number, because 66465591 - 2¹ = 66465589 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66465521) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 211 + ... + 11531.

It is an arithmetic number, because the mean of its divisors is an integer number (5887440).

Almost surely, 2^66465591 is an apocalyptic number.

66465591 is a deficient number, since it is larger than the sum of its proper divisors (27733449).

66465591 is a wasteful number, since it uses less digits than its factorization.

66465591 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11446.

The product of its digits is 194400, while the sum is 42.

The square root of 66465591 is about 8152.6431910148. The cubic root of 66465591 is about 405.0720615562.

The spelling of 66465591 in words is "sixty-six million, four hundred sixty-five thousand, five hundred ninety-one".