9920621 has 2 divisors, whose sum is σ = 9920622. Its totient is φ = 9920620.

The previous prime is 9920611. The next prime is 9920653. The reversal of 9920621 is 1260299.

9920621 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 7214596 + 2706025 = 2686^2 + 1645^2 .

It is a cyclic number.

It is not a de Polignac number, because 9920621 - 2⁶ = 9920557 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (9920611) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4960310 + 4960311.

It is an arithmetic number, because the mean of its divisors is an integer number (4960311).

Almost surely, 2^9920621 is an apocalyptic number.

It is an amenable number.

9920621 is a deficient number, since it is larger than the sum of its proper divisors (1).

9920621 is an equidigital number, since it uses as much as digits as its factorization.

9920621 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1944, while the sum is 29.

The square root of 9920621 is about 3149.7017319105. The cubic root of 9920621 is about 214.8718977287.

The spelling of 9920621 in words is "nine million, nine hundred twenty thousand, six hundred twenty-one".