67140221 has 4 divisors (see below), whose sum is σ = 67293600. Its totient is φ = 66986844.

The previous prime is 67140211. The next prime is 67140287. The reversal of 67140221 is 12204176.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 67140221 - 2²⁶ = 31357 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (67140211) 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, 76031 + ... + 76908.

It is an arithmetic number, because the mean of its divisors is an integer number (16823400).

Almost surely, 2^67140221 is an apocalyptic number.

It is an amenable number.

67140221 is a deficient number, since it is larger than the sum of its proper divisors (153379).

67140221 is a wasteful number, since it uses less digits than its factorization.

67140221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 153378.

The product of its (nonzero) digits is 672, while the sum is 23.

The square root of 67140221 is about 8193.9136558790. The cubic root of 67140221 is about 406.4379530767.

Adding to 67140221 its reverse (12204176), we get a palindrome (79344397).

The spelling of 67140221 in words is "sixty-seven million, one hundred forty thousand, two hundred twenty-one".