9921913 has 4 divisors (see below), whose sum is σ = 9929088. Its totient is φ = 9914740.

The previous prime is 9921907. The next prime is 9921917. The reversal of 9921913 is 3191299.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 9921913 - 2¹³ = 9913721 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (9921917) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 781 + ... + 4522.

It is an arithmetic number, because the mean of its divisors is an integer number (2482272).

Almost surely, 2^9921913 is an apocalyptic number.

It is an amenable number.

9921913 is a deficient number, since it is larger than the sum of its proper divisors (7175).

9921913 is a wasteful number, since it uses less digits than its factorization.

9921913 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7174.

The product of its digits is 4374, while the sum is 34.

The square root of 9921913 is about 3149.9068240188. The cubic root of 9921913 is about 214.8812251838.

The spelling of 9921913 in words is "nine million, nine hundred twenty-one thousand, nine hundred thirteen".