66868237 has 2 divisors, whose sum is σ = 66868238. Its totient is φ = 66868236.

The previous prime is 66868231. The next prime is 66868247. The reversal of 66868237 is 73286866.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 35832196 + 31036041 = 5986^2 + 5571^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-66868237 is a prime.

It is a super-2 number, since 2×66868237² = 8942722238976338, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66868231) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33434118 + 33434119.

It is an arithmetic number, because the mean of its divisors is an integer number (33434119).

Almost surely, 2^66868237 is an apocalyptic number.

It is an amenable number.

66868237 is a deficient number, since it is larger than the sum of its proper divisors (1).

66868237 is an equidigital number, since it uses as much as digits as its factorization.

66868237 is an evil number, because the sum of its binary digits is even.

The product of its digits is 580608, while the sum is 46.

The square root of 66868237 is about 8177.3001045577. The cubic root of 66868237 is about 405.8883856840. Note that the first 3 decimals are identical.

The spelling of 66868237 in words is "sixty-six million, eight hundred sixty-eight thousand, two hundred thirty-seven".