9921913037844 has 12 divisors (see below), whose sum is σ = 23151130421664. Its totient is φ = 3307304345944.

The previous prime is 9921913037837. The next prime is 9921913037873. The reversal of 9921913037844 is 4487303191299.

It is a tau number, because it is divible by the number of its divisors (12).

It is a congruent number.

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, 413413043232 + ... + 413413043255.

It is an arithmetic number, because the mean of its divisors is an integer number (1929260868472).

Almost surely, 2^{9921913037844} is an apocalyptic number.

It is an amenable number.

9921913037844 is an abundant number, since it is smaller than the sum of its proper divisors (13229217383820).

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

9921913037844 is a wasteful number, since it uses less digits than its factorization.

9921913037844 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 826826086494 (or 826826086492 counting only the distinct ones).

The product of its (nonzero) digits is 11757312, while the sum is 60.

The spelling of 9921913037844 in words is "nine trillion, nine hundred twenty-one billion, nine hundred thirteen million, thirty-seven thousand, eight hundred forty-four".