66860231 has 2 divisors, whose sum is σ = 66860232. Its totient is φ = 66860230.

The previous prime is 66860197. The next prime is 66860263. The reversal of 66860231 is 13206866.

It is an a-pointer prime, because the next prime (66860263) can be obtained adding 66860231 to its sum of digits (32).

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-66860231 is a prime.

It is a super-2 number, since 2×66860231² = 8940580978746722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66860291) by changing a digit.

It is a good prime.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33430115 + 33430116.

It is an arithmetic number, because the mean of its divisors is an integer number (33430116).

Almost surely, 2^66860231 is an apocalyptic number.

66860231 is a deficient number, since it is larger than the sum of its proper divisors (1).

66860231 is an equidigital number, since it uses as much as digits as its factorization.

66860231 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 10368, while the sum is 32.

The square root of 66860231 is about 8176.8105640280. The cubic root of 66860231 is about 405.8721863032.

The spelling of 66860231 in words is "sixty-six million, eight hundred sixty thousand, two hundred thirty-one".