19991203 has 4 divisors (see below), whose sum is σ = 20010040. Its totient is φ = 19972368.

The previous prime is 19991189. The next prime is 19991219. The reversal of 19991203 is 30219991.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 30219991 = 3119 ⋅9689.

It is a cyclic number.

It is not a de Polignac number, because 19991203 - 2⁵ = 19991171 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (19991243) 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, 7725 + ... + 9982.

It is an arithmetic number, because the mean of its divisors is an integer number (5002510).

Almost surely, 2^19991203 is an apocalyptic number.

19991203 is a deficient number, since it is larger than the sum of its proper divisors (18837).

19991203 is a wasteful number, since it uses less digits than its factorization.

19991203 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18836.

The product of its (nonzero) digits is 4374, while the sum is 34.

The square root of 19991203 is about 4471.1523123240. The cubic root of 19991203 is about 271.4019579367.

The spelling of 19991203 in words is "nineteen million, nine hundred ninety-one thousand, two hundred three".