67420664081 has 4 divisors (see below), whose sum is σ = 69065070564. Its totient is φ = 65776257600.

The previous prime is 67420664063. The next prime is 67420664141. The reversal of 67420664081 is 18046602476.

67420664081 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 17877027025 + 49543637056 = 133705^2 + 222584^2 .

It is a cyclic number.

It is not a de Polignac number, because 67420664081 - 2²² = 67416469777 is a prime.

It is a super-2 number, since 2×67420664081² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (67420664581) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 822203180 + ... + 822203261.

It is an arithmetic number, because the mean of its divisors is an integer number (17266267641).

Almost surely, 2^67420664081 is an apocalyptic number.

It is an amenable number.

67420664081 is a deficient number, since it is larger than the sum of its proper divisors (1644406483).

67420664081 is a wasteful number, since it uses less digits than its factorization.

67420664081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1644406482.

The product of its (nonzero) digits is 387072, while the sum is 44.

The spelling of 67420664081 in words is "sixty-seven billion, four hundred twenty million, six hundred sixty-four thousand, eighty-one".