19403939 has 2 divisors, whose sum is σ = 19403940. Its totient is φ = 19403938.

The previous prime is 19403831. The next prime is 19403941. The reversal of 19403939 is 93930491.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 19403939 - 2¹² = 19399843 is a prime.

Together with 19403941, 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 (19403039) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9701969 + 9701970.

It is an arithmetic number, because the mean of its divisors is an integer number (9701970).

Almost surely, 2^19403939 is an apocalyptic number.

19403939 is a deficient number, since it is larger than the sum of its proper divisors (1).

19403939 is an equidigital number, since it uses as much as digits as its factorization.

19403939 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 26244, while the sum is 38.

The square root of 19403939 is about 4404.9902383547. The cubic root of 19403939 is about 268.7179226903.

The spelling of 19403939 in words is "nineteen million, four hundred three thousand, nine hundred thirty-nine".