67666481 has 4 divisors (see below), whose sum is σ = 67924032. Its totient is φ = 67408932.

The previous prime is 67666463. The next prime is 67666493. The reversal of 67666481 is 18466676.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 67666481 - 2²² = 63472177 is a prime.

It is a super-2 number, since 2×67666481² = 9157505301846722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (67666411) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 128381 + ... + 128906.

It is an arithmetic number, because the mean of its divisors is an integer number (16981008).

Almost surely, 2^67666481 is an apocalyptic number.

It is an amenable number.

67666481 is a deficient number, since it is larger than the sum of its proper divisors (257551).

67666481 is a wasteful number, since it uses less digits than its factorization.

67666481 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 257550.

The product of its digits is 290304, while the sum is 44.

The square root of 67666481 is about 8225.9638341048. The cubic root of 67666481 is about 407.4971076363.

The spelling of 67666481 in words is "sixty-seven million, six hundred sixty-six thousand, four hundred eighty-one".