989511221 has 4 divisors (see below), whose sum is σ = 1032533472. Its totient is φ = 946488972.

The previous prime is 989511191. The next prime is 989511269. The reversal of 989511221 is 122115989.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 989511221 - 2²⁶ = 922402357 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 (989511121) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 21511091 + ... + 21511136.

It is an arithmetic number, because the mean of its divisors is an integer number (258133368).

Almost surely, 2^989511221 is an apocalyptic number.

It is an amenable number.

989511221 is a deficient number, since it is larger than the sum of its proper divisors (43022251).

989511221 is a wasteful number, since it uses less digits than its factorization.

989511221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43022250.

The product of its digits is 12960, while the sum is 38.

The square root of 989511221 is about 31456.4972779869. The cubic root of 989511221 is about 996.4914447703.

The spelling of 989511221 in words is "nine hundred eighty-nine million, five hundred eleven thousand, two hundred twenty-one".