42223121 has 4 divisors (see below), whose sum is σ = 44706852. Its totient is φ = 39739392.

The previous prime is 42223117. The next prime is 42223133. The reversal of 42223121 is 12132224.

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 37210000 + 5013121 = 6100^2 + 2239^2 .

It is a cyclic number.

It is not a de Polignac number, because 42223121 - 2² = 42223117 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (17), and also a Moran number because the ratio is a prime number: 2483713 = 42223121 / (4 + 2 + 2 + 2 + 3 + 1 + 2 + 1).

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 42223121.

It is not an unprimeable number, because it can be changed into a prime (42223171) 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, 1241840 + ... + 1241873.

It is an arithmetic number, because the mean of its divisors is an integer number (11176713).

Almost surely, 2^42223121 is an apocalyptic number.

It is an amenable number.

42223121 is a deficient number, since it is larger than the sum of its proper divisors (2483731).

42223121 is a wasteful number, since it uses less digits than its factorization.

42223121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2483730.

The product of its digits is 192, while the sum is 17.

The square root of 42223121 is about 6497.9320556620. The cubic root of 42223121 is about 348.2171130533.

Adding to 42223121 its reverse (12132224), we get a palindrome (54355345).

The spelling of 42223121 in words is "forty-two million, two hundred twenty-three thousand, one hundred twenty-one".