42443121 has 16 divisors (see below), whose sum is σ = 65404800. Its totient is φ = 23979648.

The previous prime is 42443099. The next prime is 42443179. The reversal of 42443121 is 12134424.

It is not a de Polignac number, because 42443121 - 2⁷ = 42442993 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is not an unprimeable number, because it can be changed into a prime (42441121) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9486 + ... + 13223.

It is an arithmetic number, because the mean of its divisors is an integer number (4087800).

Almost surely, 2^42443121 is an apocalyptic number.

It is an amenable number.

42443121 is a deficient number, since it is larger than the sum of its proper divisors (22961679).

42443121 is a wasteful number, since it uses less digits than its factorization.

42443121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22808.

The product of its digits is 768, while the sum is 21.

The square root of 42443121 is about 6514.8385244763. The cubic root of 42443121 is about 348.8208509589.

Adding to 42443121 its reverse (12134424), we get a palindrome (54577545).

The spelling of 42443121 in words is "forty-two million, four hundred forty-three thousand, one hundred twenty-one".