19721969206 has 16 divisors (see below), whose sum is σ = 31047616224. Its totient is φ = 9377720704.

The previous prime is 19721969203. The next prime is 19721969219. The reversal of 19721969206 is 60296912791.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19721969203) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1231171 + ... + 1247086.

It is an arithmetic number, because the mean of its divisors is an integer number (1940476014).

Almost surely, 2^19721969206 is an apocalyptic number.

19721969206 is a deficient number, since it is larger than the sum of its proper divisors (11325647018).

19721969206 is a wasteful number, since it uses less digits than its factorization.

19721969206 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2478455.

The product of its (nonzero) digits is 734832, while the sum is 52.

The spelling of 19721969206 in words is "nineteen billion, seven hundred twenty-one million, nine hundred sixty-nine thousand, two hundred six".