42628121 has 4 divisors (see below), whose sum is σ = 42814500. Its totient is φ = 42441744.

The previous prime is 42628111. The next prime is 42628123. The reversal of 42628121 is 12182624.

It is a happy number.

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 35868121 + 6760000 = 5989^2 + 2600^2 .

It is a cyclic number.

It is not a de Polignac number, because 42628121 - 2¹⁰ = 42627097 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (42628123) 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 3 ways as a sum of consecutive naturals, for example, 92846 + ... + 93303.

It is an arithmetic number, because the mean of its divisors is an integer number (10703625).

Almost surely, 2^42628121 is an apocalyptic number.

It is an amenable number.

42628121 is a deficient number, since it is larger than the sum of its proper divisors (186379).

42628121 is a wasteful number, since it uses less digits than its factorization.

42628121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 186378.

The product of its digits is 1536, while the sum is 26.

The square root of 42628121 is about 6529.0214427585. The cubic root of 42628121 is about 349.3269268738.

The spelling of 42628121 in words is "forty-two million, six hundred twenty-eight thousand, one hundred twenty-one".