66914591 has 4 divisors (see below), whose sum is σ = 66969000. Its totient is φ = 66860184.

The previous prime is 66914587. The next prime is 66914609. The reversal of 66914591 is 19541966.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 66914591 - 2² = 66914587 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66914581) 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, 25316 + ... + 27833.

It is an arithmetic number, because the mean of its divisors is an integer number (16742250).

Almost surely, 2^66914591 is an apocalyptic number.

66914591 is a deficient number, since it is larger than the sum of its proper divisors (54409).

66914591 is a wasteful number, since it uses less digits than its factorization.

66914591 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 54408.

The product of its digits is 58320, while the sum is 41.

The square root of 66914591 is about 8180.1339231091. The cubic root of 66914591 is about 405.9821531948.

The spelling of 66914591 in words is "sixty-six million, nine hundred fourteen thousand, five hundred ninety-one".