42012121 has 4 divisors (see below), whose sum is σ = 42544000. Its totient is φ = 41480244.

The previous prime is 42012119. The next prime is 42012127. The reversal of 42012121 is 12121024.

It is a happy number.

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 42012121 - 2¹ = 42012119 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (42012127) 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, 265821 + ... + 265978.

It is an arithmetic number, because the mean of its divisors is an integer number (10636000).

Almost surely, 2^42012121 is an apocalyptic number.

It is an amenable number.

42012121 is a deficient number, since it is larger than the sum of its proper divisors (531879).

42012121 is an equidigital number, since it uses as much as digits as its factorization.

42012121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 531878.

The product of its (nonzero) digits is 32, while the sum is 13.

The square root of 42012121 is about 6481.6757863997. The cubic root of 42012121 is about 347.6361000970.

Adding to 42012121 its reverse (12121024), we get a palindrome (54133145).

The spelling of 42012121 in words is "forty-two million, twelve thousand, one hundred twenty-one".