67443121 has 4 divisors (see below), whose sum is σ = 67634532. Its totient is φ = 67251712.

The previous prime is 67443109. The next prime is 67443139. The reversal of 67443121 is 12134476.

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

It can be written as a sum of positive squares in 2 ways, for example, as 51322896 + 16120225 = 7164^2 + 4015^2 .

It is a cyclic number.

It is not a de Polignac number, because 67443121 - 2²⁵ = 33888689 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 67443121.

It is not an unprimeable number, because it can be changed into a prime (67443151) 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, 95176 + ... + 95881.

It is an arithmetic number, because the mean of its divisors is an integer number (16908633).

Almost surely, 2^67443121 is an apocalyptic number.

It is an amenable number.

67443121 is a deficient number, since it is larger than the sum of its proper divisors (191411).

67443121 is a wasteful number, since it uses less digits than its factorization.

67443121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 191410.

The product of its digits is 4032, while the sum is 28.

The square root of 67443121 is about 8212.3760873452. The cubic root of 67443121 is about 407.0482448992.

Adding to 67443121 its reverse (12134476), we get a palindrome (79577597).

The spelling of 67443121 in words is "sixty-seven million, four hundred forty-three thousand, one hundred twenty-one".