9721123 has 2 divisors, whose sum is σ = 9721124. Its totient is φ = 9721122.

The previous prime is 9721091. The next prime is 9721133. The reversal of 9721123 is 3211279.

It is a strong prime.

It is an emirp because it is prime and its reverse (3211279) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 9721123 - 2⁵ = 9721091 is a prime.

It is a super-2 number, since 2×9721123² = 189000464762258, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (9721133) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4860561 + 4860562.

It is an arithmetic number, because the mean of its divisors is an integer number (4860562).

Almost surely, 2^9721123 is an apocalyptic number.

9721123 is a deficient number, since it is larger than the sum of its proper divisors (1).

9721123 is an equidigital number, since it uses as much as digits as its factorization.

9721123 is an evil number, because the sum of its binary digits is even.

The product of its digits is 756, while the sum is 25.

The square root of 9721123 is about 3117.8715496313. The cubic root of 9721123 is about 213.4218168648.

The spelling of 9721123 in words is "nine million, seven hundred twenty-one thousand, one hundred twenty-three".