19490421 has 4 divisors (see below), whose sum is σ = 25987232. Its totient is φ = 12993612.

The previous prime is 19490417. The next prime is 19490431. The reversal of 19490421 is 12409491.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 12409491 = 3 ⋅4136497.

It is not a de Polignac number, because 19490421 - 2² = 19490417 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19490411) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3248401 + ... + 3248406.

It is an arithmetic number, because the mean of its divisors is an integer number (6496808).

Almost surely, 2^19490421 is an apocalyptic number.

It is an amenable number.

19490421 is a deficient number, since it is larger than the sum of its proper divisors (6496811).

19490421 is an equidigital number, since it uses as much as digits as its factorization.

19490421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6496810.

The product of its (nonzero) digits is 2592, while the sum is 30.

The square root of 19490421 is about 4414.7956917620. The cubic root of 19490421 is about 269.1165500578.

The spelling of 19490421 in words is "nineteen million, four hundred ninety thousand, four hundred twenty-one".