42120043320221 has 2 divisors, whose sum is σ = 42120043320222. Its totient is φ = 42120043320220.

The previous prime is 42120043320217. The next prime is 42120043320367. The reversal of 42120043320221 is 12202334002124.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 40640752500100 + 1479290820121 = 6375010^2 + 1216261^2 .

It is a cyclic number.

It is not a de Polignac number, because 42120043320221 - 2² = 42120043320217 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (42120043322221) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21060021660110 + 21060021660111.

It is an arithmetic number, because the mean of its divisors is an integer number (21060021660111).

Almost surely, 2^{42120043320221} is an apocalyptic number.

It is an amenable number.

42120043320221 is a deficient number, since it is larger than the sum of its proper divisors (1).

42120043320221 is an equidigital number, since it uses as much as digits as its factorization.

42120043320221 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4608, while the sum is 26.

Adding to 42120043320221 its reverse (12202334002124), we get a palindrome (54322377322345).

The spelling of 42120043320221 in words is "forty-two trillion, one hundred twenty billion, forty-three million, three hundred twenty thousand, two hundred twenty-one".