42009403 has 2 divisors, whose sum is σ = 42009404. Its totient is φ = 42009402.

The previous prime is 42009391. The next prime is 42009413. The reversal of 42009403 is 30490024.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 42009403 - 2⁹ = 42008891 is a prime.

It is not a weakly prime, because it can be changed into another prime (42009413) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21004701 + 21004702.

It is an arithmetic number, because the mean of its divisors is an integer number (21004702).

Almost surely, 2^42009403 is an apocalyptic number.

42009403 is a deficient number, since it is larger than the sum of its proper divisors (1).

42009403 is an equidigital number, since it uses as much as digits as its factorization.

42009403 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 864, while the sum is 22.

The square root of 42009403 is about 6481.4661150082. The cubic root of 42009403 is about 347.6286030915.

Adding to 42009403 its reverse (30490024), we get a palindrome (72499427).

The spelling of 42009403 in words is "forty-two million, nine thousand, four hundred three".