66841531 has 2 divisors, whose sum is σ = 66841532. Its totient is φ = 66841530.

The previous prime is 66841529. The next prime is 66841547. The reversal of 66841531 is 13514866.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 66841531 - 2¹ = 66841529 is a prime.

It is a super-2 number, since 2×66841531² = 8935580532847922, which contains 22 as substring.

Together with 66841529, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (66841561) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33420765 + 33420766.

It is an arithmetic number, because the mean of its divisors is an integer number (33420766).

Almost surely, 2^66841531 is an apocalyptic number.

66841531 is a deficient number, since it is larger than the sum of its proper divisors (1).

66841531 is an equidigital number, since it uses as much as digits as its factorization.

66841531 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 17280, while the sum is 34.

The square root of 66841531 is about 8175.6670064283. The cubic root of 66841531 is about 405.8343435903.

The spelling of 66841531 in words is "sixty-six million, eight hundred forty-one thousand, five hundred thirty-one".