67664419 has 2 divisors, whose sum is σ = 67664420. Its totient is φ = 67664418.

The previous prime is 67664417. The next prime is 67664423. The reversal of 67664419 is 91446676.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 67664419 - 2¹ = 67664417 is a prime.

It is a super-2 number, since 2×67664419² = 9156947197215122, which contains 22 as substring.

Together with 67664417, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (67664417) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33832209 + 33832210.

It is an arithmetic number, because the mean of its divisors is an integer number (33832210).

Almost surely, 2^67664419 is an apocalyptic number.

67664419 is a deficient number, since it is larger than the sum of its proper divisors (1).

67664419 is an equidigital number, since it uses as much as digits as its factorization.

67664419 is an evil number, because the sum of its binary digits is even.

The product of its digits is 217728, while the sum is 43.

The square root of 67664419 is about 8225.8384982930. The cubic root of 67664419 is about 407.4929683758.

The spelling of 67664419 in words is "sixty-seven million, six hundred sixty-four thousand, four hundred nineteen".