66231617 has 4 divisors (see below), whose sum is σ = 66574980. Its totient is φ = 65888256.

The previous prime is 66231533. The next prime is 66231619. The reversal of 66231617 is 71613266.

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

It can be written as a sum of positive squares in 2 ways, for example, as 37405456 + 28826161 = 6116^2 + 5369^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-66231617 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66231619) 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, 171392 + ... + 171777.

It is an arithmetic number, because the mean of its divisors is an integer number (16643745).

Almost surely, 2^66231617 is an apocalyptic number.

It is an amenable number.

66231617 is a deficient number, since it is larger than the sum of its proper divisors (343363).

66231617 is a wasteful number, since it uses less digits than its factorization.

66231617 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 343362.

The product of its digits is 9072, while the sum is 32.

The square root of 66231617 is about 8138.2809609892. The cubic root of 66231617 is about 404.5961874560.

The spelling of 66231617 in words is "sixty-six million, two hundred thirty-one thousand, six hundred seventeen".