19721945748 has 24 divisors (see below), whose sum is σ = 46326722400. Its totient is φ = 6529860640.

The previous prime is 19721945731. The next prime is 19721945767. The reversal of 19721945748 is 84754912791.

It is a congruent number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 5513298 + ... + 5516873.

It is an arithmetic number, because the mean of its divisors is an integer number (1930280100).

Almost surely, 2^19721945748 is an apocalyptic number.

It is an amenable number.

19721945748 is an abundant number, since it is smaller than the sum of its proper divisors (26604776652).

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

19721945748 is a wasteful number, since it uses less digits than its factorization.

19721945748 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11030327 (or 11030325 counting only the distinct ones).

The product of its digits is 5080320, while the sum is 57.

The spelling of 19721945748 in words is "nineteen billion, seven hundred twenty-one million, nine hundred forty-five thousand, seven hundred forty-eight".