42013121 has 2 divisors, whose sum is σ = 42013122. Its totient is φ = 42013120.

The previous prime is 42013109. The next prime is 42013163. The reversal of 42013121 is 12131024.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 39942400 + 2070721 = 6320^2 + 1439^2 .

It is a cyclic number.

It is not a de Polignac number, because 42013121 - 2⁶ = 42013057 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 42013096 and 42013105.

It is not a weakly prime, because it can be changed into another prime (42015121) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21006560 + 21006561.

It is an arithmetic number, because the mean of its divisors is an integer number (21006561).

Almost surely, 2^42013121 is an apocalyptic number.

It is an amenable number.

42013121 is a deficient number, since it is larger than the sum of its proper divisors (1).

42013121 is an equidigital number, since it uses as much as digits as its factorization.

42013121 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 48, while the sum is 14.

The square root of 42013121 is about 6481.7529264852. The cubic root of 42013121 is about 347.6388582957.

Adding to 42013121 its reverse (12131024), we get a palindrome (54144145).

The spelling of 42013121 in words is "forty-two million, thirteen thousand, one hundred twenty-one".