42222421 has 2 divisors, whose sum is σ = 42222422. Its totient is φ = 42222420.

The previous prime is 42222409. The next prime is 42222437. The reversal of 42222421 is 12422224.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 25502500 + 16719921 = 5050^2 + 4089^2 .

It is a cyclic number.

It is not a de Polignac number, because 42222421 - 2⁹ = 42221909 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (42222221) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21111210 + 21111211.

It is an arithmetic number, because the mean of its divisors is an integer number (21111211).

Almost surely, 2^42222421 is an apocalyptic number.

It is an amenable number.

42222421 is a deficient number, since it is larger than the sum of its proper divisors (1).

42222421 is an equidigital number, since it uses as much as digits as its factorization.

42222421 is an evil number, because the sum of its binary digits is even.

The product of its digits is 512, while the sum is 19.

The square root of 42222421 is about 6497.8781921486. The cubic root of 42222421 is about 348.2151887259.

Adding to 42222421 its reverse (12422224), we get a palindrome (54644645).

The spelling of 42222421 in words is "forty-two million, two hundred twenty-two thousand, four hundred twenty-one".