9977221 has 4 divisors (see below), whose sum is σ = 10140844. Its totient is φ = 9813600.

The previous prime is 9977213. The next prime is 9977237. The reversal of 9977221 is 1227799.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1227799 = 19 ⋅64621.

It can be written as a sum of positive squares in 2 ways, for example, as 893025 + 9084196 = 945^2 + 3014^2 .

It is a cyclic number.

It is not a de Polignac number, because 9977221 - 2³ = 9977213 is a prime.

It is a Duffinian number.

It is a nialpdrome in base 10.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9977251) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 81720 + ... + 81841.

It is an arithmetic number, because the mean of its divisors is an integer number (2535211).

Almost surely, 2^9977221 is an apocalyptic number.

It is an amenable number.

9977221 is a deficient number, since it is larger than the sum of its proper divisors (163623).

9977221 is a wasteful number, since it uses less digits than its factorization.

9977221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 163622.

The product of its digits is 15876, while the sum is 37.

The square root of 9977221 is about 3158.6739306234. The cubic root of 9977221 is about 215.2797584087.

The spelling of 9977221 in words is "nine million, nine hundred seventy-seven thousand, two hundred twenty-one".