67740021 has 12 divisors (see below), whose sum is σ = 97974240. Its totient is φ = 45101160.

The previous prime is 67740017. The next prime is 67740059. The reversal of 67740021 is 12004776.

It is not a de Polignac number, because 67740021 - 2² = 67740017 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (67740011) 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 11 ways as a sum of consecutive naturals, for example, 3066 + ... + 12036.

It is an arithmetic number, because the mean of its divisors is an integer number (8164520).

Almost surely, 2^67740021 is an apocalyptic number.

It is an amenable number.

67740021 is a deficient number, since it is larger than the sum of its proper divisors (30234219).

67740021 is a wasteful number, since it uses less digits than its factorization.

67740021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9816 (or 9813 counting only the distinct ones).

The product of its (nonzero) digits is 2352, while the sum is 27.

The square root of 67740021 is about 8230.4326131741. The cubic root of 67740021 is about 407.6446769459.

Adding to 67740021 its reverse (12004776), we get a palindrome (79744797).

The spelling of 67740021 in words is "sixty-seven million, seven hundred forty thousand, twenty-one".