66157216 has 12 divisors (see below), whose sum is σ = 130247082. Its totient is φ = 33078592.

The previous prime is 66157211. The next prime is 66157229. The reversal of 66157216 is 61275166.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 38489616 + 27667600 = 6204^2 + 5260^2 .

It is not an unprimeable number, because it can be changed into a prime (66157211) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1033675 + ... + 1033738.

Almost surely, 2^66157216 is an apocalyptic number.

It is an amenable number.

66157216 is a deficient number, since it is larger than the sum of its proper divisors (64089866).

66157216 is a wasteful number, since it uses less digits than its factorization.

66157216 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2067423 (or 2067415 counting only the distinct ones).

The product of its digits is 15120, while the sum is 34.

The square root of 66157216 is about 8133.7086252213. The cubic root of 66157216 is about 404.4446302333. Note that the first 3 decimals are identical.

It can be divided in two parts, 6615 and 7216, that added together give a palindrome (13831).

The spelling of 66157216 in words is "sixty-six million, one hundred fifty-seven thousand, two hundred sixteen".