67445681 has 8 divisors (see below), whose sum is σ = 71737344. Its totient is φ = 63190080.

The previous prime is 67445671. The next prime is 67445699. The reversal of 67445681 is 18654476.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-67445681 is a prime.

It is a super-2 number, since 2×67445681² = 9097839771107522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (67445641) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5105 + ... + 12686.

It is an arithmetic number, because the mean of its divisors is an integer number (8967168).

Almost surely, 2^67445681 is an apocalyptic number.

It is an amenable number.

67445681 is a deficient number, since it is larger than the sum of its proper divisors (4291663).

67445681 is a wasteful number, since it uses less digits than its factorization.

67445681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18031.

The product of its digits is 161280, while the sum is 41.

The square root of 67445681 is about 8212.5319481875. The cubic root of 67445681 is about 407.0533950678.

The spelling of 67445681 in words is "sixty-seven million, four hundred forty-five thousand, six hundred eighty-one".