42004451 has 2 divisors, whose sum is σ = 42004452. Its totient is φ = 42004450.

The previous prime is 42004439. The next prime is 42004453. The reversal of 42004451 is 15440024.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 42004451 - 2⁶ = 42004387 is a prime.

It is a super-2 number, since 2×42004451² = 3528747807622802, which contains 22 as substring.

Together with 42004453, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (42004453) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21002225 + 21002226.

It is an arithmetic number, because the mean of its divisors is an integer number (21002226).

Almost surely, 2^42004451 is an apocalyptic number.

42004451 is a deficient number, since it is larger than the sum of its proper divisors (1).

42004451 is an equidigital number, since it uses as much as digits as its factorization.

42004451 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 640, while the sum is 20.

The square root of 42004451 is about 6481.0840914156. The cubic root of 42004451 is about 347.6149432570.

Adding to 42004451 its reverse (15440024), we get a palindrome (57444475).

The spelling of 42004451 in words is "forty-two million, four thousand, four hundred fifty-one".