19903423 has 2 divisors, whose sum is σ = 19903424. Its totient is φ = 19903422.

The previous prime is 19903421. The next prime is 19903439. The reversal of 19903423 is 32430991.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 19903423 - 2¹ = 19903421 is a prime.

It is a super-2 number, since 2×19903423² = 792292494233858, which contains 22 as substring.

Together with 19903421, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (19903421) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9951711 + 9951712.

It is an arithmetic number, because the mean of its divisors is an integer number (9951712).

Almost surely, 2^19903423 is an apocalyptic number.

19903423 is a deficient number, since it is larger than the sum of its proper divisors (1).

19903423 is an equidigital number, since it uses as much as digits as its factorization.

19903423 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5832, while the sum is 31.

The square root of 19903423 is about 4461.3252515368. The cubic root of 19903423 is about 271.0041393140.

The spelling of 19903423 in words is "nineteen million, nine hundred three thousand, four hundred twenty-three".