67145981 has 8 divisors (see below), whose sum is σ = 80777280. Its totient is φ = 54524448.

The previous prime is 67145977. The next prime is 67145999. The reversal of 67145981 is 18954176.

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

It is a cyclic number.

It is not a de Polignac number, because 67145981 - 2² = 67145977 is a prime.

It is a super-3 number, since 3×67145981³ (a number of 24 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (67145951) 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, 252296 + ... + 252561.

It is an arithmetic number, because the mean of its divisors is an integer number (10097160).

Almost surely, 2^67145981 is an apocalyptic number.

It is an amenable number.

67145981 is a deficient number, since it is larger than the sum of its proper divisors (13631299).

67145981 is a wasteful number, since it uses less digits than its factorization.

67145981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 504883.

The product of its digits is 60480, while the sum is 41.

The square root of 67145981 is about 8194.2651287349. The cubic root of 67145981 is about 406.4495755966.

The spelling of 67145981 in words is "sixty-seven million, one hundred forty-five thousand, nine hundred eighty-one".