66520193 has 8 divisors (see below), whose sum is σ = 67320000. Its totient is φ = 65724048.

The previous prime is 66520177. The next prime is 66520211. The reversal of 66520193 is 39102566.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 66520193 - 2⁴ = 66520177 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66526193) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 53780 + ... + 55002.

It is an arithmetic number, because the mean of its divisors is an integer number (8415000).

Almost surely, 2^66520193 is an apocalyptic number.

It is an amenable number.

66520193 is a deficient number, since it is larger than the sum of its proper divisors (799807).

66520193 is a wasteful number, since it uses less digits than its factorization.

66520193 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1831.

The product of its (nonzero) digits is 9720, while the sum is 32.

The square root of 66520193 is about 8155.9912334431. The cubic root of 66520193 is about 405.1829544784.

The spelling of 66520193 in words is "sixty-six million, five hundred twenty thousand, one hundred ninety-three".