67028991 has 8 divisors (see below), whose sum is σ = 89972400. Its totient is φ = 44385792.

The previous prime is 67028989. The next prime is 67028993. The reversal of 67028991 is 19982076.

It is an interprime number because it is at equal distance from previous prime (67028989) and next prime (67028993).

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

It is not a de Polignac number, because 67028991 - 2¹ = 67028989 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (67028993) 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, 74530 + ... + 75423.

It is an arithmetic number, because the mean of its divisors is an integer number (11246550).

Almost surely, 2^67028991 is an apocalyptic number.

67028991 is a deficient number, since it is larger than the sum of its proper divisors (22943409).

67028991 is a wasteful number, since it uses less digits than its factorization.

67028991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 150105.

The product of its (nonzero) digits is 54432, while the sum is 42.

The square root of 67028991 is about 8187.1234875260. The cubic root of 67028991 is about 406.2133828614.

The spelling of 67028991 in words is "sixty-seven million, twenty-eight thousand, nine hundred ninety-one".