67388991 has 16 divisors (see below), whose sum is σ = 94755840. Its totient is φ = 42482880.

The previous prime is 67388989. The next prime is 67389013. The reversal of 67388991 is 19988376.

It is not a de Polignac number, because 67388991 - 2¹ = 67388989 is a prime.

It is a super-2 number, since 2×67388991² = 9082552215996162, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (67388491) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 55891 + ... + 57083.

It is an arithmetic number, because the mean of its divisors is an integer number (5922240).

Almost surely, 2^67388991 is an apocalyptic number.

67388991 is a deficient number, since it is larger than the sum of its proper divisors (27366849).

67388991 is a wasteful number, since it uses less digits than its factorization.

67388991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2206.

The product of its digits is 653184, while the sum is 51.

The square root of 67388991 is about 8209.0797900861. The cubic root of 67388991 is about 406.9393164742.

The spelling of 67388991 in words is "sixty-seven million, three hundred eighty-eight thousand, nine hundred ninety-one".