66157205 has 8 divisors (see below), whose sum is σ = 79495992. Its totient is φ = 52854208.

The previous prime is 66157181. The next prime is 66157211. The reversal of 66157205 is 50275166.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 6543364 + 59613841 = 2558^2 + 7721^2 .

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 66157205 - 2⁶ = 66157141 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4694 + ... + 12423.

It is an arithmetic number, because the mean of its divisors is an integer number (9936999).

Almost surely, 2^66157205 is an apocalyptic number.

It is an amenable number.

66157205 is a deficient number, since it is larger than the sum of its proper divisors (13338787).

66157205 is a wasteful number, since it uses less digits than its factorization.

66157205 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17895.

The product of its (nonzero) digits is 12600, while the sum is 32.

The square root of 66157205 is about 8133.7079490230. The cubic root of 66157205 is about 404.4446078176. Note that the first 3 decimals are identical.

The spelling of 66157205 in words is "sixty-six million, one hundred fifty-seven thousand, two hundred five".