42400416221 has 4 divisors (see below), whose sum is σ = 42837534012. Its totient is φ = 41963298432.

The previous prime is 42400416199. The next prime is 42400416229. The reversal of 42400416221 is 12261400424.

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 28228704196 + 14171712025 = 168014^2 + 119045^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-42400416221 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (42400416229) 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 3 ways as a sum of consecutive naturals, for example, 218558750 + ... + 218558943.

It is an arithmetic number, because the mean of its divisors is an integer number (10709383503).

Almost surely, 2^42400416221 is an apocalyptic number.

It is an amenable number.

42400416221 is a deficient number, since it is larger than the sum of its proper divisors (437117791).

42400416221 is an equidigital number, since it uses as much as digits as its factorization.

42400416221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 437117790.

The product of its (nonzero) digits is 3072, while the sum is 26.

Adding to 42400416221 its reverse (12261400424), we get a palindrome (54661816645).

The spelling of 42400416221 in words is "forty-two billion, four hundred million, four hundred sixteen thousand, two hundred twenty-one".