19219855 has 4 divisors (see below), whose sum is σ = 23063832. Its totient is φ = 15375880.

The previous prime is 19219853. The next prime is 19219883. The reversal of 19219855 is 55891291.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 19219855 - 2¹ = 19219853 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19219853) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1921981 + ... + 1921990.

It is an arithmetic number, because the mean of its divisors is an integer number (5765958).

Almost surely, 2^19219855 is an apocalyptic number.

19219855 is a deficient number, since it is larger than the sum of its proper divisors (3843977).

19219855 is an equidigital number, since it uses as much as digits as its factorization.

19219855 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3843976.

The product of its digits is 32400, while the sum is 40.

The square root of 19219855 is about 4384.0455061507. The cubic root of 19219855 is about 267.8654509508.

The spelling of 19219855 in words is "nineteen million, two hundred nineteen thousand, eight hundred fifty-five".