67921609 has 16 divisors (see below), whose sum is σ = 80014720. Its totient is φ = 56453760.

The previous prime is 67921583. The next prime is 67921643. The reversal of 67921609 is 90612976.

It is a cyclic number.

It is not a de Polignac number, because 67921609 - 2⁹ = 67921097 is a prime.

It is a super-2 number, since 2×67921609² = 9226689938297762, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (67921109) 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, 30082 + ... + 32260.

It is an arithmetic number, because the mean of its divisors is an integer number (5000920).

Almost surely, 2^67921609 is an apocalyptic number.

It is an amenable number.

67921609 is a deficient number, since it is larger than the sum of its proper divisors (12093111).

67921609 is a wasteful number, since it uses less digits than its factorization.

67921609 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2320.

The product of its (nonzero) digits is 40824, while the sum is 40.

The square root of 67921609 is about 8241.4567280305. The cubic root of 67921609 is about 408.0086042816.

The spelling of 67921609 in words is "sixty-seven million, nine hundred twenty-one thousand, six hundred nine".