67991011 has 4 divisors (see below), whose sum is σ = 74172024. Its totient is φ = 61810000.

The previous prime is 67991009. The next prime is 67991047. The reversal of 67991011 is 11019976.

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

It is a cyclic number.

It is not a de Polignac number, because 67991011 - 2¹ = 67991009 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (67992011) 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, 3090490 + ... + 3090511.

It is an arithmetic number, because the mean of its divisors is an integer number (18543006).

Almost surely, 2^67991011 is an apocalyptic number.

67991011 is a deficient number, since it is larger than the sum of its proper divisors (6181013).

67991011 is a wasteful number, since it uses less digits than its factorization.

67991011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6181012.

The product of its (nonzero) digits is 3402, while the sum is 34.

The square root of 67991011 is about 8245.6661950385. Note that the first 3 decimals coincide. The cubic root of 67991011 is about 408.1475241062.

The spelling of 67991011 in words is "sixty-seven million, nine hundred ninety-one thousand, eleven".