42001222210021 has 2 divisors, whose sum is σ = 42001222210022. Its totient is φ = 42001222210020.

The previous prime is 42001222209997. The next prime is 42001222210063. The reversal of 42001222210021 is 12001222210024.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 34906531830625 + 7094690379396 = 5908175^2 + 2663586^2 .

It is a cyclic number.

It is not a de Polignac number, because 42001222210021 - 2²⁵ = 42001188655589 is a prime.

It is a super-2 number, since 2×42001222210021² (a number of 28 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (42001222610021) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21000611105010 + 21000611105011.

It is an arithmetic number, because the mean of its divisors is an integer number (21000611105011).

Almost surely, 2^{42001222210021} is an apocalyptic number.

It is an amenable number.

42001222210021 is a deficient number, since it is larger than the sum of its proper divisors (1).

42001222210021 is an equidigital number, since it uses as much as digits as its factorization.

42001222210021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 256, while the sum is 19.

Adding to 42001222210021 its reverse (12001222210024), we get a palindrome (54002444420045).

The spelling of 42001222210021 in words is "forty-two trillion, one billion, two hundred twenty-two million, two hundred ten thousand, twenty-one".