19721834 has 8 divisors (see below), whose sum is σ = 32272128. Its totient is φ = 8964460.

The previous prime is 19721813. The next prime is 19721843. The reversal of 19721834 is 43812791.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a junction number, because it is equal to n+sod(n) for n = 19721794 and 19721803.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 448202 + ... + 448245.

It is an arithmetic number, because the mean of its divisors is an integer number (4034016).

Almost surely, 2^19721834 is an apocalyptic number.

19721834 is a deficient number, since it is larger than the sum of its proper divisors (12550294).

19721834 is a wasteful number, since it uses less digits than its factorization.

19721834 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 896460.

The product of its digits is 12096, while the sum is 35.

The square root of 19721834 is about 4440.9271554485. The cubic root of 19721834 is about 270.1774507933.

The spelling of 19721834 in words is "nineteen million, seven hundred twenty-one thousand, eight hundred thirty-four".