64666471 has 4 divisors (see below), whose sum is σ = 66243744. Its totient is φ = 63089200.

The previous prime is 64666451. The next prime is 64666489. The reversal of 64666471 is 17466646.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 17466646 = 2 ⋅8733323.

It is a cyclic number.

It is not a de Polignac number, because 64666471 - 2⁹ = 64665959 is a prime.

It is a super-3 number, since 3×64666471³ (a number of 24 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64666451) 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, 788575 + ... + 788656.

It is an arithmetic number, because the mean of its divisors is an integer number (16560936).

Almost surely, 2^64666471 is an apocalyptic number.

64666471 is a deficient number, since it is larger than the sum of its proper divisors (1577273).

64666471 is a wasteful number, since it uses less digits than its factorization.

64666471 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1577272.

The product of its digits is 145152, while the sum is 40.

The square root of 64666471 is about 8041.5465552343. The cubic root of 64666471 is about 401.3836892410.

The spelling of 64666471 in words is "sixty-four million, six hundred sixty-six thousand, four hundred seventy-one".