8997821 has 12 divisors (see below), whose sum is σ = 10692288. Its totient is φ = 7546392.

The previous prime is 8997803. The next prime is 8997847. The reversal of 8997821 is 1287998.

It is not a de Polignac number, because 8997821 - 2¹⁰ = 8996797 is a prime.

It is a Smith number, since the sum of its digits (44) coincides with the sum of the digits of its prime factors.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8997871) 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 11 ways as a sum of consecutive naturals, for example, 350 + ... + 4256.

It is an arithmetic number, because the mean of its divisors is an integer number (891024).

Almost surely, 2^8997821 is an apocalyptic number.

It is an amenable number.

8997821 is a deficient number, since it is larger than the sum of its proper divisors (1694467).

8997821 is a wasteful number, since it uses less digits than its factorization.

8997821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3968 (or 3961 counting only the distinct ones).

The product of its digits is 72576, while the sum is 44.

The square root of 8997821 is about 2999.6368113490. The cubic root of 8997821 is about 207.9915939034.

The spelling of 8997821 in words is "eight million, nine hundred ninety-seven thousand, eight hundred twenty-one".