19902243 has 4 divisors (see below), whose sum is σ = 26536328. Its totient is φ = 13268160.

The previous prime is 19902241. The next prime is 19902299. The reversal of 19902243 is 34220991.

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

It is not a de Polignac number, because 19902243 - 2¹ = 19902241 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 19902243.

It is not an unprimeable number, because it can be changed into a prime (19902241) 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, 3317038 + ... + 3317043.

It is an arithmetic number, because the mean of its divisors is an integer number (6634082).

Almost surely, 2^19902243 is an apocalyptic number.

19902243 is a deficient number, since it is larger than the sum of its proper divisors (6634085).

19902243 is an equidigital number, since it uses as much as digits as its factorization.

19902243 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6634084.

The product of its (nonzero) digits is 3888, while the sum is 30.

The square root of 19902243 is about 4461.1930018774. The cubic root of 19902243 is about 270.9987835986.

The spelling of 19902243 in words is "nineteen million, nine hundred two thousand, two hundred forty-three".