42003421 has 2 divisors, whose sum is σ = 42003422. Its totient is φ = 42003420.

The previous prime is 42003407. The next prime is 42003463. The reversal of 42003421 is 12430024.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 41100921 + 902500 = 6411^2 + 950^2 .

It is a cyclic number.

It is not a de Polignac number, because 42003421 - 2¹³ = 41995229 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 42003395 and 42003404.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (42003491) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21001710 + 21001711.

It is an arithmetic number, because the mean of its divisors is an integer number (21001711).

Almost surely, 2^42003421 is an apocalyptic number.

It is an amenable number.

42003421 is a deficient number, since it is larger than the sum of its proper divisors (1).

42003421 is an equidigital number, since it uses as much as digits as its factorization.

42003421 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 192, while the sum is 16.

The square root of 42003421 is about 6481.0046289136. The cubic root of 42003421 is about 347.6121019206.

Adding to 42003421 its reverse (12430024), we get a palindrome (54433445).

It can be divided in two parts, 42003 and 421, that added together give a palindrome (42424).

The spelling of 42003421 in words is "forty-two million, three thousand, four hundred twenty-one".