42420040121 has 6 divisors (see below), whose sum is σ = 43832571066. Its totient is φ = 41051650800.

The previous prime is 42420040031. The next prime is 42420040139. The reversal of 42420040121 is 12104002424.

It can be written as a sum of positive squares in only one way, i.e., 42306319225 + 113720896 = 205685^2 + 10664^2 .

It is a de Polignac number, because none of the positive numbers 2^k-42420040121 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 42420040093 and 42420040102.

It is not an unprimeable number, because it can be changed into a prime (42420040171) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 22069820 + ... + 22071741.

It is an arithmetic number, because the mean of its divisors is an integer number (7305428511).

Almost surely, 2^42420040121 is an apocalyptic number.

It is an amenable number.

42420040121 is a deficient number, since it is larger than the sum of its proper divisors (1412530945).

42420040121 is an equidigital number, since it uses as much as digits as its factorization.

42420040121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 44141623 (or 44141592 counting only the distinct ones).

The product of its (nonzero) digits is 512, while the sum is 20.

Adding to 42420040121 its reverse (12104002424), we get a palindrome (54524042545).

The spelling of 42420040121 in words is "forty-two billion, four hundred twenty million, forty thousand, one hundred twenty-one".