67991889 has 8 divisors (see below), whose sum is σ = 103606720. Its totient is φ = 38852496.

The previous prime is 67991873. The next prime is 67991909. The reversal of 67991889 is 98819976.

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

It is not a de Polignac number, because 67991889 - 2⁴ = 67991873 is a prime.

It is not an unprimeable number, because it can be changed into a prime (67991839) 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, 1618834 + ... + 1618875.

It is an arithmetic number, because the mean of its divisors is an integer number (12950840).

Almost surely, 2^67991889 is an apocalyptic number.

It is an amenable number.

67991889 is a deficient number, since it is larger than the sum of its proper divisors (35614831).

67991889 is a wasteful number, since it uses less digits than its factorization.

67991889 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3237719.

The product of its digits is 1959552, while the sum is 57.

The square root of 67991889 is about 8245.7194349553. The cubic root of 67991889 is about 408.1492809658.

The spelling of 67991889 in words is "sixty-seven million, nine hundred ninety-one thousand, eight hundred eighty-nine".