42404431 has 2 divisors, whose sum is σ = 42404432. Its totient is φ = 42404430.

The previous prime is 42404419. The next prime is 42404471. The reversal of 42404431 is 13440424.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 42404431 - 2⁹ = 42403919 is a prime.

It is a super-2 number, since 2×42404431² = 3596271536867522, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (42404471) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21202215 + 21202216.

It is an arithmetic number, because the mean of its divisors is an integer number (21202216).

Almost surely, 2^42404431 is an apocalyptic number.

42404431 is a deficient number, since it is larger than the sum of its proper divisors (1).

42404431 is an equidigital number, since it uses as much as digits as its factorization.

42404431 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1536, while the sum is 22.

The square root of 42404431 is about 6511.8684722589. The cubic root of 42404431 is about 348.7148268549.

Adding to 42404431 its reverse (13440424), we get a palindrome (55844855).

The spelling of 42404431 in words is "forty-two million, four hundred four thousand, four hundred thirty-one".