9819721934 has 16 divisors (see below), whose sum is σ = 17013850416. Its totient is φ = 4200950400.

The previous prime is 9819721931. The next prime is 9819721943. The reversal of 9819721934 is 4391279189.

It is a super-2 number, since 2×9819721934² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9819721931) 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, 13127597 + ... + 13128344.

It is an arithmetic number, because the mean of its divisors is an integer number (1063365651).

Almost surely, 2^9819721934 is an apocalyptic number.

9819721934 is a deficient number, since it is larger than the sum of its proper divisors (7194128482).

9819721934 is a wasteful number, since it uses less digits than its factorization.

9819721934 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26255971.

The product of its digits is 979776, while the sum is 53.

The square root of 9819721934 is about 99094.5101102982. The cubic root of 9819721934 is about 2141.4095245730.

The spelling of 9819721934 in words is "nine billion, eight hundred nineteen million, seven hundred twenty-one thousand, nine hundred thirty-four".