42422021 has 12 divisors (see below), whose sum is σ = 45331620. Its totient is φ = 39690240.

The previous prime is 42422011. The next prime is 42422027. The reversal of 42422021 is 12022424.

It is a happy number.

It can be written as a sum of positive squares in 6 ways, for example, as 21390625 + 21031396 = 4625^2 + 4586^2 .

It is not a de Polignac number, because 42422021 - 2⁶ = 42421957 is a prime.

It is a super-3 number, since 3×42422021³ (a number of 24 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (17).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (42422027) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 65861 + ... + 66501.

It is an arithmetic number, because the mean of its divisors is an integer number (3777635).

Almost surely, 2^42422021 is an apocalyptic number.

It is an amenable number.

42422021 is a deficient number, since it is larger than the sum of its proper divisors (2909599).

42422021 is a wasteful number, since it uses less digits than its factorization.

42422021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 904 (or 887 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 17.

The square root of 42422021 is about 6513.2189430419. The cubic root of 42422021 is about 348.7630375859.

Adding to 42422021 its reverse (12022424), we get a palindrome (54444445).

The spelling of 42422021 in words is "forty-two million, four hundred twenty-two thousand, twenty-one".