66894469 has 2 divisors, whose sum is σ = 66894470. Its totient is φ = 66894468.

The previous prime is 66894467. The next prime is 66894479. The reversal of 66894469 is 96449866.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 66422500 + 471969 = 8150^2 + 687^2 .

It is a cyclic number.

It is not a de Polignac number, because 66894469 - 2¹ = 66894467 is a prime.

It is a super-2 number, since 2×66894469² = 8949739965583922, which contains 22 as substring.

Together with 66894467, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66894463) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33447234 + 33447235.

It is an arithmetic number, because the mean of its divisors is an integer number (33447235).

Almost surely, 2^66894469 is an apocalyptic number.

It is an amenable number.

66894469 is a deficient number, since it is larger than the sum of its proper divisors (1).

66894469 is an equidigital number, since it uses as much as digits as its factorization.

66894469 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2239488, while the sum is 52.

The square root of 66894469 is about 8178.9038996677. The cubic root of 66894469 is about 405.9414545880.

The spelling of 66894469 in words is "sixty-six million, eight hundred ninety-four thousand, four hundred sixty-nine".