66997031 has 2 divisors, whose sum is σ = 66997032. Its totient is φ = 66997030.

The previous prime is 66997013. The next prime is 66997033. The reversal of 66997031 is 13079966.

It is a happy number.

Together with previous prime (66997013) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-66997031 is a prime.

It is a super-2 number, since 2×66997031² = 8977204325629922, which contains 22 as substring.

Together with 66997033, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 66997031.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66997033) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33498515 + 33498516.

It is an arithmetic number, because the mean of its divisors is an integer number (33498516).

Almost surely, 2^66997031 is an apocalyptic number.

66997031 is a deficient number, since it is larger than the sum of its proper divisors (1).

66997031 is an equidigital number, since it uses as much as digits as its factorization.

66997031 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 61236, while the sum is 41.

The square root of 66997031 is about 8185.1714093231. The cubic root of 66997031 is about 406.1488105846.

The spelling of 66997031 in words is "sixty-six million, nine hundred ninety-seven thousand, thirty-one".