19721802 has 32 divisors (see below), whose sum is σ = 41990400. Its totient is φ = 6153728.

The previous prime is 19721771. The next prime is 19721809. The reversal of 19721802 is 20812791.

It is a self number, because there is not a number n which added to its sum of digits gives 19721802.

It is not an unprimeable number, because it can be changed into a prime (19721809) 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 15 ways as a sum of consecutive naturals, for example, 23974 + ... + 24782.

It is an arithmetic number, because the mean of its divisors is an integer number (1312200).

Almost surely, 2^19721802 is an apocalyptic number.

19721802 is an abundant number, since it is smaller than the sum of its proper divisors (22268598).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

19721802 is a wasteful number, since it uses less digits than its factorization.

19721802 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1070.

The product of its (nonzero) digits is 2016, while the sum is 30.

The square root of 19721802 is about 4440.9235525958. The cubic root of 19721802 is about 270.1773046662.

The spelling of 19721802 in words is "nineteen million, seven hundred twenty-one thousand, eight hundred two".