9661021 has 4 divisors (see below), whose sum is σ = 9668412. Its totient is φ = 9653632.

The previous prime is 9661019. The next prime is 9661037. The reversal of 9661021 is 1201669.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 5616900 + 4044121 = 2370^2 + 2011^2 .

It is a cyclic number.

It is not a de Polignac number, because 9661021 - 2¹ = 9661019 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9662021) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1150 + ... + 4543.

It is an arithmetic number, because the mean of its divisors is an integer number (2417103).

Almost surely, 2^9661021 is an apocalyptic number.

It is an amenable number.

9661021 is a deficient number, since it is larger than the sum of its proper divisors (7391).

9661021 is a wasteful number, since it uses less digits than its factorization.

9661021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7390.

The product of its (nonzero) digits is 648, while the sum is 25.

The square root of 9661021 is about 3108.2182999268. The cubic root of 9661021 is about 212.9810720321.

Adding to 9661021 its product of nonzero digits (648), we get a palindrome (9661669).

The spelling of 9661021 in words is "nine million, six hundred sixty-one thousand, twenty-one".